/* vax780_stddev.c: VAX 11/780 standard I/O devices

   Copyright (c) 1998-2012, Robert M Supnik

   Permission is hereby granted, free of charge, to any person obtaining a
   copy of this software and associated documentation files (the "Software"),
   to deal in the Software without restriction, including without limitation
   the rights to use, copy, modify, merge, publish, distribute, sublicense,
   and/or sell copies of the Software, and to permit persons to whom the
   Software is furnished to do so, subject to the following conditions:

   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   ROBERT M SUPNIK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
   IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

   Except as contained in this notice, the name of Robert M Supnik shall not be
   used in advertising or otherwise to promote the sale, use or other dealings
   in this Software without prior written authorization from Robert M Supnik.

   tti          console input
   tto          console output
   cs           console floppy
   todr         TODR clock
   tmr          interval timer

   18-Apr-12    RMS     Revised to use clock coscheduling
   28-Sep-11    MP      Generalized setting TODR for all OSes.  
                        Unbound the TODR value from the 100hz clock tick 
                        interrupt.  TODR now behaves like the original 
                        battery backed-up clock and runs with the wall 
                        clock, not the simulated instruction clock.  
                        Two operational modes are available:
                        - Default VMS mode, which is similar to the previous 
                          behavior in that without initializing the TODR it 
                          would default to the value VMS would set it to if
                          VMS knew the correct time.  This would be correct
                          almost all the time unless a VMS disk hadn't been
                          booted from for more than a year.  This mode 
                          produces strange time results for non VMS OSes on 
                          each system boot.
                        - OS Agnostic mode.  This mode behaves precisely like
                          the VAX780 TODR and works correctly for all OSes.  
                          This mode is enabled by attaching the TODR to a 
                          battery backup state file for the TOY clock 
                          (i.e. sim> attach TODR TOY_CLOCK).  When operating 
                          in OS Agnostic mode, the TODR will initially start
                          counting from 0 and be adjusted differently when an
                          OS specifically writes to the TODR.  VMS will prompt
                          to set the time on each boot unless the SYSGEN 
                          parameter TIMEPROMPTWAIT is set to 0.
   21-Mar-11    RMS     Added reboot capability
   17-Aug-08    RMS     Resync TODR on any clock reset
   18-Jun-07    RMS     Added UNIT_IDLE flag to console input, clock
   29-Oct-06    RMS     Added clock coscheduler function
                        Synced keyboard to clock for idling
   11-May-06    RMS     Revised timer logic for EVKAE
   22-Nov-05    RMS     Revised for new terminal processing routines
   10-Mar-05    RMS     Fixed bug in timer schedule routine (Mark Hittinger)
   08-Sep-04    RMS     Cloned from vax_stddev.c, vax_sysdev.c, and pdp11_rx.c

   The console floppy protocol is based on the description in the 1982 VAX
   Architecture Reference Manual:

   TXDB<11:8> = 0       ->      normal console output
   TXDB<11:8> = 1       ->      data output to floppy
   TXDB<11:8> = 3       ->      read communications region
   TXDB<11:8> = 9       ->      command output to floppy
   TXDB<11:8> = F       ->      flag output (e.g., reboot)

   RXDB<11:8> = 0       ->      normal terminal input
   RXDB<11:8> = 1       ->      data input from floppy
   RXDB<11:8> = 3       ->      communications region data
   RXDB<11:8> = 2       ->      status input from floppy
   RXDB<11:8> = 9       ->      "command" input from floppy (protocol error)
*/

#include "vax_defs.h"
#include "sim_tmxr.h"

/* Terminal definitions */

#define RXCS_RD         (CSR_DONE + CSR_IE)             /* terminal input */
#define RXCS_WR         (CSR_IE)
#define RXDB_ERR        0x8000                          /* error */
#define RXDB_OVR        0x4000                          /* overrun */
#define RXDB_FRM        0x2000                          /* framing error */
#define TXCS_RD         (CSR_DONE + CSR_IE)             /* terminal output */
#define TXCS_WR         (CSR_IE)
#define TXDB_V_SEL      8                               /* unit select */
#define TXDB_M_SEL      0xF
#define  TXDB_FDAT      0x1                             /* floppy data */
#define  TXDB_COMM      0x3                             /* console mem read */
#define  TXDB_FCMD      0x9                             /* floppy cmd */
#define  TXDB_MISC      0xF                             /* console misc */
#define COMM_LNT        0200                            /* comm region lnt */
#define COMM_MASK       (COMM_LNT - 1)                  /* comm region mask */
#define  COMM_GH        0144                            /* GH flag */
#define  COMM_WRMS      0145                            /* warm start */
#define  COMM_CLDS      0146                            /* cold start */
#define  COMM_APTL      0147                            /* APT load */
#define  COMM_LAST      0150                            /* last position */
#define  COMM_AUTO      0151                            /* auto restart */
#define  COMM_PCSV      0152                            /* PCS version */
#define  COMM_WCSV      0153                            /* WCS version */
#define  COMM_WCSS      0154                            /* WCS secondary */
#define  COMM_FPLV      0155                            /* FPLA version */
#define  COMM_MTCH_785  0153                            /* 785 PCS/WCS version */
#define  COMM_WCSP_785  0154                            /* 785 WCS version */
#define  COMM_WCSS_785  0155                            /* 785 WCS secondary */
#define COMM_DATA       0x300                           /* comm data return */
#define MISC_MASK        0xFF                           /* console data mask */
#define  MISC_SWDN       0x1                            /* software done */
#define  MISC_BOOT       0x2                            /* reboot */
#define  MISC_CLWS       0x3                            /* clear warm start */
#define  MISC_CLCS       0x4                            /* clear cold start */
#define TXDB_SEL        (TXDB_M_SEL << TXDB_V_SEL)      /* non-terminal */
#define TXDB_GETSEL(x)  (((x) >> TXDB_V_SEL) & TXDB_M_SEL)

/* Clock definitions */

#define TMR_CSR_ERR     0x80000000                      /* error W1C */
#define TMR_CSR_DON     0x00000080                      /* done W1C */
#define TMR_CSR_IE      0x00000040                      /* int enb RW */
#define TMR_CSR_SGL     0x00000020                      /* single WO */
#define TMR_CSR_XFR     0x00000010                      /* xfer WO */
#define TMR_CSR_RUN     0x00000001                      /* run RW */
#define TMR_CSR_RD      (TMR_CSR_W1C | TMR_CSR_WR)
#define TMR_CSR_W1C     (TMR_CSR_ERR | TMR_CSR_DON)
#define TMR_CSR_WR      (TMR_CSR_IE | TMR_CSR_RUN)
#define TMR_INC         10000                           /* usec/interval */
#define CLK_DELAY       5000                            /* 100 Hz */
#define TMXR_MULT       1                               /* 100 Hz */

static BITFIELD tmr_iccs_bits [] = {
    BIT(RUN),                                   /* Run */
    BITNCF(3),                                  /* unused */
    BIT(XFR),                                   /* Transfer */
    BIT(SGL),                                   /* Single */
    BIT(IE),                                    /* Interrupt Enable */
    BIT(DON),                                   /* Done */
    BITNCF(23),                                 /* unused */
    BIT(ERR),                                   /* Error */
    ENDBITS
    };

/* Floppy definitions */

#define FL_NUMTR        77                              /* tracks/disk */
#define FL_M_TRACK      0377
#define FL_NUMSC        26                              /* sectors/track */
#define FL_M_SECTOR     0177
#define FL_NUMBY        128                             /* bytes/sector */
#define FL_SIZE         (FL_NUMTR * FL_NUMSC * FL_NUMBY)        /* bytes/disk */
#define UNIT_V_WLK      (UNIT_V_UF)                     /* write locked */
#define UNIT_WLK        (1u << UNIT_V_UF)
#define UNIT_WPRT       (UNIT_WLK | UNIT_RO)            /* write protect */

#define FL_IDLE         0                               /* idle state */
#define FL_RWDS         1                               /* rw, sect next */
#define FL_RWDT         2                               /* rw, track next */
#define FL_READ         3                               /* read */
#define FL_READ1        4
#define FL_WRITE        5                               /* write */
#define FL_WRITE1       6
#define FL_FILL         7                               /* fill buffer */
#define FL_EMPTY        8                               /* empty buffer */
#define FL_READSTA      9                               /* read status */
#define FL_DONE         10                              /* cmd done */

#define FL_V_FNC        0                               /* floppy function */
#define FL_M_FNC        0xFF
#define  FL_FNCRD       0x0                             /* read */
#define  FL_FNCWR       0x1                             /* write */
#define  FL_FNCRS       0x2                             /* read status */
#define  FL_FNCWD       0x3                             /* write del data */
#define  FL_FNCCA       0x4                             /* cancel */
#define FL_CDATA        0x100                           /* returned data */
#define FL_CDONE        0x200                           /* completion code */
#define  FL_STACRC      0x001                           /* status bits */
#define  FL_STAPAR      0x002
#define  FL_STAINC      0x004
#define  FL_STADDA      0x040
#define  FL_STAERR      0x080
#define FL_CPROT        0x905                           /* protocol error */
#define FL_GETFNC(x)    (((x) >> FL_V_FNC) & FL_M_FNC)

#define TRACK u3                                        /* current track */
#define CALC_DA(t,s) (((t) * FL_NUMSC) + ((s) - 1)) * FL_NUMBY

int32 tti_csr = 0;                                      /* control/status */
uint32 tti_buftime;                                     /* time input character arrived */
int32 tti_buf = 0;                                      /* buffer */
int32 tti_int = 0;                                      /* interrupt */
int32 tto_csr = 0;                                      /* control/status */
int32 tto_buf = 0;                                      /* buffer */
int32 tto_int = 0;                                      /* interrupt */

int32 tmr_iccs = 0;                                     /* interval timer csr */
uint32 tmr_icr = 0;                                     /* curr interval */
uint32 tmr_nicr = 0;                                    /* next interval */
uint32 tmr_inc = 0;                                     /* timer increment */
int32 tmr_int = 0;                                      /* interrupt */
int32 clk_tps = 100;                                    /* ticks/second */
int32 tmxr_poll = CLK_DELAY * TMXR_MULT;                /* term mux poll */
int32 tmr_poll = CLK_DELAY;                             /* pgm timer poll */
struct todr_battery_info {
    uint32 toy_gmtbase;                                 /* GMT base of set value */
    uint32 toy_gmtbasemsec;                             /* The milliseconds of the set value */
    uint32 toy_endian_plus2;                            /* 2 -> Big Endian, 3 -> Little Endian, invalid otherwise */
    };
typedef struct todr_battery_info TOY;

int32 fl_fnc = 0;                                       /* function */
int32 fl_esr = 0;                                       /* error status */
int32 fl_ecode = 0;                                     /* error code */
int32 fl_track = 0;                                     /* desired track */
int32 fl_sector = 0;                                    /* desired sector */
int32 fl_state = FL_IDLE;                               /* controller state */
int32 fl_stopioe = 1;                                   /* stop on error */
int32 fl_swait = 100;                                   /* seek, per track */
int32 fl_cwait = 50;                                    /* command time */
int32 fl_xwait = 20;                                    /* tr set time */
uint8 fl_buf[FL_NUMBY] = { 0 };                         /* sector buffer */
int32 fl_bptr = 0;                                      /* buffer pointer */

uint8 comm_region[COMM_LNT] = { 0 };                    /* comm region */

t_stat tti_svc (UNIT *uptr);
t_stat tto_svc (UNIT *uptr);
t_stat tmr_svc (UNIT *uptr);
t_stat clk_svc (UNIT *uptr);
t_stat tti_reset (DEVICE *dptr);
t_stat tto_reset (DEVICE *dptr);
t_stat clk_reset (DEVICE *dptr);
const char *tti_description (DEVICE *dptr);
const char *tto_description (DEVICE *dptr);
const char *clk_description (DEVICE *dptr);
const char *tmr_description (DEVICE *dptr);
const char *fl_description (DEVICE *dptr);
t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr);
t_stat clk_attach (UNIT *uptr, CONST char *cptr);
t_stat clk_detach (UNIT *uptr);
t_stat tmr_reset (DEVICE *dptr);
t_stat fl_svc (UNIT *uptr);
t_stat fl_reset (DEVICE *dptr);
int32 icr_rd (void);
void tmr_sched (uint32 incr);
t_stat todr_resync (void);
t_stat fl_wr_txdb (int32 data);
t_bool fl_test_xfr (UNIT *uptr, t_bool wr);
void fl_protocol_error (void);

extern int32 con_halt (int32 code, int32 cc);

/* TTI data structures

   tti_dev      TTI device descriptor
   tti_unit     TTI unit descriptor
   tti_reg      TTI register list
*/

UNIT tti_unit = { UDATA (&tti_svc, UNIT_IDLE|TT_MODE_8B, 0), TMLN_SPD_9600_BPS };

REG tti_reg[] = {
    { HRDATAD (RXDB,       tti_buf,         16, "last data item processed") },
    { HRDATAD (RXCS,       tti_csr,         16, "control/status register") },
    { FLDATAD (INT,        tti_int,          0, "interrupt pending flag") },
    { FLDATAD (DONE,       tti_csr, CSR_V_DONE, "device done flag (CSR<7>)") },
    { FLDATAD (IE,         tti_csr,   CSR_V_IE, "interrupt enable flag (CSR<6>)") },
    { DRDATAD (POS,   tti_unit.pos,   T_ADDR_W, "number of characters input"), PV_LEFT },
    { DRDATAD (TIME, tti_unit.wait,         24, "input polling interval"), PV_LEFT },
    { NULL }
    };

MTAB tti_mod[] = {
    { TT_MODE,  TT_MODE_7B, "7b", "7B",     NULL, NULL,      NULL, "Set 7 bit mode" },
    { TT_MODE,  TT_MODE_8B, "8b", "8B",     NULL, NULL,      NULL, "Set 8 bit mode" },
    { 0 }
    };

DEVICE tti_dev = {
    "TTI", &tti_unit, tti_reg, tti_mod,
    1, 10, 31, 1, 16, 8,
    NULL, NULL, &tti_reset,
    NULL, NULL, NULL,
    NULL, 0, 0, NULL, NULL, NULL, &tti_help, NULL, NULL, 
    &tti_description
    };

/* TTO data structures

   tto_dev      TTO device descriptor
   tto_unit     TTO unit descriptor
   tto_reg      TTO register list
*/

UNIT tto_unit = { UDATA (&tto_svc, TT_MODE_8B, 0), SERIAL_OUT_WAIT };

REG tto_reg[] = {
    { HRDATAD (TXDB,       tto_buf,         16, "last data item processed") },
    { HRDATAD (TXCS,       tto_csr,         16, "control/status register") },
    { FLDATAD (INT,        tto_int,          0, "interrupt pending flag") },
    { FLDATAD (DONE,       tto_csr, CSR_V_DONE, "device done flag (CSR<7>)") },
    { FLDATAD (IE,         tto_csr,   CSR_V_IE, "interrupt enable flag (CSR<6>)") },
    { DRDATAD (POS,   tto_unit.pos,   T_ADDR_W, "number of characters output"), PV_LEFT },
    { DRDATAD (TIME, tto_unit.wait,         24, "time from I/O initiation to interrupt"), PV_LEFT + REG_NZ },
    { NULL }
    };

MTAB tto_mod[] = {
    { TT_MODE,  TT_MODE_7B, "7b", "7B",     NULL, NULL,      NULL, "Set 7 bit mode" },
    { TT_MODE,  TT_MODE_8B, "8b", "8B",     NULL, NULL,      NULL, "Set 8 bit mode" },
    { TT_MODE,  TT_MODE_7P, "7p", "7P",     NULL, NULL,      NULL, "Set 7 bit mode (suppress non printing output)" },
    { 0 }
    };

DEVICE tto_dev = {
    "TTO", &tto_unit, tto_reg, tto_mod,
    1, 10, 31, 1, 16, 8,
    NULL, NULL, &tto_reset,
    NULL, NULL, NULL,
    NULL, 0, 0, NULL, NULL, NULL, &tto_help, NULL, NULL, 
    &tto_description
    };

/* TODR and TMR data structures */

UNIT clk_unit = { UDATA (&clk_svc, UNIT_FIX, sizeof(TOY))};

REG clk_reg[] = {
    { DRDATAD (TIME,                   clk_unit.wait,  24, "initial poll interval"), REG_NZ + PV_LEFT },
    { DRDATAD (POLL,                        tmr_poll,  24, "calibrated poll interval"), REG_NZ + PV_LEFT + REG_HRO },
#if defined (SIM_ASYNCH_IO)
    { DRDATAD (ASYNCH,            sim_asynch_enabled,   1, "asynch I/O enabled flag"), PV_LEFT },
    { DRDATAD (LATENCY,           sim_asynch_latency,  32, "desired asynch interrupt latency"), PV_LEFT },
    { DRDATAD (INST_LATENCY, sim_asynch_inst_latency,  32, "calibrated instruction latency"), PV_LEFT },
#endif
    { NULL }
    };

#define TMR_DB_TODR     0x10    /* TODR */

DEBTAB todr_deb[] = {
    { "TODR",  TMR_DB_TODR,     "TODR activities"},
    { NULL, 0 }
    };

DEVICE clk_dev = {
    "TODR", &clk_unit, clk_reg, NULL,
    1, 0, 8, 4, 0, 32,
    NULL, NULL, &clk_reset,
    NULL, &clk_attach, &clk_detach,
    NULL, DEV_DEBUG, 0, todr_deb, NULL, NULL, &clk_help, NULL, NULL, 
    &clk_description
    };

UNIT tmr_unit = { UDATA (&tmr_svc, 0, 0) };                     /* timer */

REG tmr_reg[] = {
    { HRDATADF (ICCS,         tmr_iccs, 32, "interval timer control and status", tmr_iccs_bits) },
    { HRDATAD  (ICR,           tmr_icr, 32, "interval count register") },
    { HRDATAD  (NICR,         tmr_nicr, 32, "next interval count register") },
    { FLDATAD  (INT,           tmr_int,  0, "interrupt request") },
    { DRDATAD  (TPS,           clk_tps,  8, "ticks per second"), REG_NZ + PV_LEFT },
    { HRDATA   (INCR,          tmr_inc, 32), REG_HIDDEN },
    { NULL }
    };

#define TMR_DB_REG      0x01    /* Register Access */
#define TMR_DB_TICK     0x02    /* Ticks */
#define TMR_DB_SCHED    0x04    /* Scheduling */
#define TMR_DB_INT      0x08    /* Interrupts */

DEBTAB tmr_deb[] = {
    { "REG",   TMR_DB_REG,      "Register Access"},
    { "TICK",  TMR_DB_TICK,     "Ticks"},
    { "SCHED", TMR_DB_SCHED,    "Scheduling"},
    { "INT",   TMR_DB_INT,      "Interrupts"},
    { NULL, 0 }
    };

DEVICE tmr_dev = {
    "TMR", &tmr_unit, tmr_reg, NULL,
    1, 0, 0, 0, 0, 0,
    NULL, NULL, &tmr_reset,
    NULL, NULL, NULL,
    NULL, DEV_DEBUG, 0, 
    tmr_deb, NULL, NULL, NULL, NULL, NULL, 
    &tmr_description
    };

/* RX01 data structures

   fl_dev       RX device descriptor
   fl_unit      RX unit list
   fl_reg       RX register list
   fl_mod       RX modifier list
*/

UNIT fl_unit = { UDATA (&fl_svc,
      UNIT_FIX+UNIT_ATTABLE+UNIT_BUFABLE+UNIT_MUSTBUF, FL_SIZE) };

REG fl_reg[] = {
    { HRDATAD (FNC,          fl_fnc,  8, "function select") },
    { HRDATAD (ES,           fl_esr,  8, "error status") },
    { HRDATAD (ECODE,      fl_ecode,  8, "error code") },
    { HRDATAD (TA,         fl_track,  8, "track address") },
    { HRDATAD (SA,        fl_sector,  8, "sector address") },
    { DRDATAD (PSTATE,     fl_state,  4, "protocol state"), REG_RO },
    { DRDATAD (BPTR,        fl_bptr,  7, "data buffer pointer")  },
    { DRDATAD (CTIME,      fl_cwait, 24, "command initiation delay"), PV_LEFT },
    { DRDATAD (STIME,      fl_swait, 24, "seek time delay, per track"), PV_LEFT },
    { DRDATAD (XTIME,      fl_xwait, 24, "transfer time delay, per byte"), PV_LEFT },
    { FLDATAD (STOP_IOE, fl_stopioe,  0, "stop on I/O error") },
    { BRDATAD (DBUF,         fl_buf, 16, 8, FL_NUMBY, "data buffer") },
    { BRDATAD (COMM,    comm_region, 16, 8, COMM_LNT, "comm region") },
    { NULL }
    };

MTAB fl_mod[] = {
    { UNIT_WLK,         0, "write enabled",  "WRITEENABLED", NULL, NULL, NULL, "Write enable floppy drive" },
    { UNIT_WLK,  UNIT_WLK, "write locked",   "LOCKED", NULL, NULL, NULL, "Write lock floppy drive"  },
    { 0 }
    };

DEVICE fl_dev = {
    "CS", &fl_unit, fl_reg, fl_mod,
    1, DEV_RDX, 20, 1, DEV_RDX, 8,
    NULL, NULL, &fl_reset,
    NULL, NULL, NULL,
    NULL, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, 
    &fl_description
    };

/* Terminal MxPR routines

   rxcs_rd/wr   input control/status
   rxdb_rd      input buffer
   txcs_rd/wr   output control/status
   txdb_wr      output buffer
*/

int32 rxcs_rd (void)
{
return (tti_csr & RXCS_RD);
}

void rxcs_wr (int32 data)
{
if ((data & CSR_IE) == 0)
    tti_int = 0;
else {
    if ((tti_csr & (CSR_DONE + CSR_IE)) == CSR_DONE)
        tti_int = 1;
    }
tti_csr = (tti_csr & ~RXCS_WR) | (data & RXCS_WR);
}

int32 rxdb_rd (void)
{
int32 t = tti_buf;                                      /* char + error */

if (tti_csr & CSR_DONE) {                               /* Input pending ? */
    tti_csr = tti_csr & ~CSR_DONE;                      /* clr done */
    tti_buf = tti_buf & BMASK;                          /* clr errors */
    tti_int = 0;
    sim_activate_after_abs (&tti_unit, tti_unit.wait);  /* check soon for more input */
    }
return t;
}

int32 txcs_rd (void)
{
return (tto_csr & TXCS_RD);
}

void txcs_wr (int32 data)
{
if ((data & CSR_IE) == 0)
    tto_int = 0;
else {
    if ((tto_csr & (CSR_DONE + CSR_IE)) == CSR_DONE)
        tto_int = 1;
    }
tto_csr = (tto_csr & ~TXCS_WR) | (data & TXCS_WR);
}

void txdb_wr (int32 data)
{
tto_buf = data & WMASK;                                 /* save data */
tto_csr = tto_csr & ~CSR_DONE;                          /* clear flag */
tto_int = 0;                                            /* clear int */
if (tto_buf & TXDB_SEL)                                 /* floppy? */
    fl_wr_txdb (tto_buf);
else
    sim_activate (&tto_unit, tto_unit.wait);           /* no, console */
}

/* Terminal input service (poll for character) */

t_stat tti_svc (UNIT *uptr)
{
int32 c;

sim_clock_coschedule (uptr, tmxr_poll);                 /* continue poll */

if ((tti_csr & CSR_DONE) &&                             /* input still pending and < 500ms? */
    ((sim_os_msec () - tti_buftime) < 500))
     return SCPE_OK;
if ((c = sim_poll_kbd ()) < SCPE_KFLAG)                 /* no char or error? */
    return c;
if (c & SCPE_BREAK)                                     /* break? */
    tti_buf = RXDB_ERR | RXDB_FRM;
else
    tti_buf = sim_tt_inpcvt (c, TT_GET_MODE (uptr->flags));
tti_buftime = sim_os_msec ();
uptr->pos = uptr->pos + 1;
tti_csr = tti_csr | CSR_DONE;
if (tti_csr & CSR_IE)
    tti_int = 1;
return SCPE_OK;
}

/* Terminal input reset */

t_stat tti_reset (DEVICE *dptr)
{
tmxr_set_console_units (&tti_unit, &tto_unit);
tti_buf = 0;
tti_csr = 0;
tti_int = 0;
sim_activate (&tti_unit, tmr_poll);
return SCPE_OK;
}

t_stat tti_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
{
fprintf (st, "Console Terminal Input (TTI)\n\n");
fprintf (st, "The terminal input (TTI) polls the console keyboard for input.\n\n");
fprint_set_help (st, dptr);
fprint_show_help (st, dptr);
fprint_reg_help (st, dptr);
return SCPE_OK;
}

const char *tti_description (DEVICE *dptr)
{
return "console terminal input";
}

/* Terminal output service (output character) */

t_stat tto_svc (UNIT *uptr)
{
int32 c;
t_stat r;

if ((tto_buf & TXDB_SEL) == 0) {                        /* for console? */
    c = sim_tt_outcvt (tto_buf, TT_GET_MODE (uptr->flags));
    if (c >= 0) {
        if ((r = sim_putchar_s (c)) != SCPE_OK) {       /* output; error? */
            sim_activate (uptr, uptr->wait);            /* retry */
            return ((r == SCPE_STALL)? SCPE_OK: r);     /* !stall? report */
            }
        }
    uptr->pos = uptr->pos + 1;
    }
tto_csr = tto_csr | CSR_DONE;
if (tto_csr & CSR_IE)
    tto_int = 1;
return SCPE_OK;
}

/* Terminal output reset */

t_stat tto_reset (DEVICE *dptr)
{
tto_buf = 0;
tto_csr = CSR_DONE;
tto_int = 0;
sim_cancel (&tto_unit);                                 /* deactivate unit */
return SCPE_OK;
}

t_stat tto_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
{
fprintf (st, "Console Terminal Output (TTO)\n\n");
fprintf (st, "The terminal output (TTO) writes to the simulator console.\n\n");
fprint_set_help (st, dptr);
fprint_show_help (st, dptr);
fprint_reg_help (st, dptr);
return SCPE_OK;
}

const char *tto_description (DEVICE *dptr)
{
return "console terminal output";
}

/* Programmable timer

   The architected VAX timer, which increments at 1Mhz, cannot be
   accurately simulated due to the overhead that would be required
   for 1M clock events per second.  Instead 1Mhz intervals are 
   derived from the calibrated instruction execution rate.

   If the interval register is read, then its value between events
   is interpolated relative to the elapsed instruction count.
*/

int32 iccs_rd (void)
{
sim_debug_bits_hdr (TMR_DB_REG, &tmr_dev, "iccs_rd()", tmr_iccs_bits, tmr_iccs, tmr_iccs, TRUE);
return tmr_iccs & TMR_CSR_RD;
}

void iccs_wr (int32 val)
{
sim_debug_bits_hdr (TMR_DB_REG, &tmr_dev, "iccs_wr()", tmr_iccs_bits, tmr_iccs, val, TRUE);
if ((val & TMR_CSR_RUN) == 0) {                         /* clearing run? */
    if (tmr_iccs & TMR_CSR_RUN) {                       /* run 1 -> 0? */
        tmr_icr = icr_rd ();                            /* update icr */
        sim_debug (TMR_DB_REG, &tmr_dev, "iccs_wr() - stopped clock with remaining ICR=0x%08X\n", tmr_icr);
        }
    sim_cancel (&tmr_unit);                             /* cancel timer */
    }
if ((tmr_iccs & CSR_DONE) && (val & CSR_DONE) &&        /* Interrupt Acked? */
    (10000 == (tmr_nicr) ? (~tmr_nicr + 1) : 0xFFFFFFFF))/* of 10ms tick */
    sim_rtcn_tick_ack (20, TMR_CLK);                    /* Let timers know */
tmr_iccs = tmr_iccs & ~(val & TMR_CSR_W1C);             /* W1C csr */
tmr_iccs = (tmr_iccs & ~TMR_CSR_WR) |                   /* new r/w */
    (val & TMR_CSR_WR);
if (val & TMR_CSR_XFR)                                  /* xfr set? */
    tmr_icr = tmr_nicr;
if (val & TMR_CSR_RUN)  {                               /* run? */
    if (val & TMR_CSR_XFR)                              /* new tir? */
        sim_cancel (&tmr_unit);                         /* stop prev */
    if (!sim_is_active (&tmr_unit))                     /* not running? */
        tmr_sched (tmr_icr);                            /* activate */
    }
else {
    if (val & TMR_CSR_XFR)                              /* xfr set? */
        tmr_icr = tmr_nicr;
    if (val & TMR_CSR_SGL) {                            /* single step? */
        tmr_icr = tmr_icr + 1;                          /* incr tmr */
        if (tmr_icr == 0) {                             /* if ovflo, */
            if (tmr_iccs & TMR_CSR_DON)                 /* done? set err */
                tmr_iccs = tmr_iccs | TMR_CSR_ERR;
            else
                tmr_iccs = tmr_iccs | TMR_CSR_DON;      /* set done */
            if (tmr_iccs & TMR_CSR_IE) {                /* ie? */
                tmr_int = 1;                            /* set int req */
                sim_debug (TMR_DB_INT, &tmr_dev, "tmr_incr() - INT=1\n");
                }
            tmr_icr = tmr_nicr;                         /* reload tir */
            }
        }
    }
if ((tmr_iccs & (TMR_CSR_DON | TMR_CSR_IE)) !=          /* update int */
    (TMR_CSR_DON | TMR_CSR_IE)) {
    if (tmr_int) {
        tmr_int = 0;
        sim_debug (TMR_DB_INT, &tmr_dev, "iccs_wr() - INT=0\n");
        }
    }
}

int32 icr_rd (void)
{
int32 result;

if (tmr_iccs & TMR_CSR_RUN) {                           /* running? */
    uint32 usecs_remaining = (uint32)sim_activate_time_usecs (&tmr_unit);

    result = (int32)(~usecs_remaining + 1);
    }
else
    result = (int32)tmr_icr;
sim_debug (TMR_DB_REG, &tmr_dev, "icr_rd() = 0x%08X%s\n", result, (tmr_iccs & TMR_CSR_RUN) ? " - interpolated" : "");
return result;
}

int32 nicr_rd (void)
{
sim_debug (TMR_DB_REG, &tmr_dev, "nicr_rd() = 0x%08X\n", tmr_nicr);
return tmr_nicr;
}

void nicr_wr (int32 val)
{
sim_debug (TMR_DB_REG, &tmr_dev, "nicr_wr(0x%08X)\n", val);
tmr_nicr = val;
}

/* Interval timer unit service */

t_stat tmr_svc (UNIT *uptr)
{
sim_debug (TMR_DB_TICK, &tmr_dev, "tmr_svc()\n");
tmxr_poll = tmr_poll * TMXR_MULT;                   /* set mux poll */
if (tmr_iccs & TMR_CSR_DON)                         /* done? set err */
    tmr_iccs = tmr_iccs | TMR_CSR_ERR;
else
    tmr_iccs = tmr_iccs | TMR_CSR_DON;              /* set done */
if (tmr_iccs & TMR_CSR_RUN)                         /* run? */
    tmr_sched (tmr_nicr);                           /* reactivate */
if (tmr_iccs & TMR_CSR_IE) {                        /* ie? set int req */
    tmr_int = 1;
    sim_debug (TMR_DB_INT, &tmr_dev, "tmr_svc() - INT=1\n");
    }
else
    tmr_int = 0;
AIO_SET_INTERRUPT_LATENCY(tmr_poll*clk_tps);        /* set interrrupt latency */
return SCPE_OK;
}

/* Timer scheduling */

void tmr_sched (uint32 nicr)
{
double usecs = (nicr) ? (double)(~nicr + 1) : (double)0x100000000LL;

sim_debug (TMR_DB_SCHED, &tmr_dev, "tmr_sched(nicr=0x%08X-usecs=%.0f) - tps=%d\n", nicr, usecs, clk_tps);
if (usecs == 10000.0)
    sim_clock_coschedule_tmr (&tmr_unit, TMR_CLK, 1);
else
    sim_activate_after_d (&tmr_unit, usecs);
}

/* 100Hz TODR reset */

t_stat clk_reset (DEVICE *dptr)
{
if (clk_unit.filebuf == NULL) {                         /* make sure the TODR is initialized */
    clk_unit.filebuf = calloc(sizeof(TOY), 1);
    if (clk_unit.filebuf == NULL)
        return SCPE_MEM;
    }
todr_resync ();
sim_activate_after (&clk_unit, 10000);
tmr_poll = sim_rtcn_init_unit (&clk_unit, CLK_DELAY, TMR_CLK);  /* init timer */
return SCPE_OK;
}

t_stat clk_svc (UNIT *uptr)
{
sim_activate_after (uptr, 10000);
tmr_poll = sim_rtcn_calb (100, TMR_CLK);
tmxr_poll = tmr_poll * TMXR_MULT;                       /* set mux poll */
return SCPE_OK;
}

t_stat clk_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag, const char *cptr)
{
fprintf (st, "Real-Time Clock (%s)\n\n", dptr->name);
fprintf (st, "The real-time clock autocalibrates; the clock interval is adjusted up or down\n");
fprintf (st, "so that the clock tracks actual elapsed time.\n\n");
fprintf (st, "There are two modes of TODR operation:\n\n");
fprintf (st, "   Default VMS mode.  Without initializing the TODR it returns the current\n");
fprintf (st, "                      time of year offset which VMS would set the clock to\n");
fprintf (st, "                      if VMS knew the correct time (i.e. by manual input).\n");
fprintf (st, "                      This is correct almost all the time unless a VMS disk\n");
fprintf (st, "                      hadn't been booted from in the current year.  This mode\n");
fprintf (st, "                      produces strange time results for non VMS OSes on each\n");
fprintf (st, "                      system boot.\n");
fprintf (st, "   OS Agnostic mode.  This mode behaves precisely like the VAX780 TODR and\n");
fprintf (st, "                      works correctly for all OSes.  This mode is enabled by\n");
fprintf (st, "                      attaching the %s to a battery backup state file for the\n", dptr->name);
fprintf (st, "                      TOY clock (i.e. sim> attach %s TOY_CLOCK).  When\n", dptr->name);
fprintf (st, "                      operating in OS Agnostic mode, the TODR will initially\n");
fprintf (st, "                      start counting from 0 and be adjusted differently when\n");
fprintf (st, "                      an OS specifically writes to the TODR.  VMS determines\n");
fprintf (st, "                      if the TODR currently contains a valid time if the value\n");
fprintf (st, "                      it sees is less than about 1 month.  If the time isn't\n");
fprintf (st, "                      valid VMS will prompt to set the time during the system\n");
fprintf (st, "                      boot.  While prompting for the time it will wait for an\n");
fprintf (st, "                      answer to the prompt for up to the SYSGEN parameter\n");
fprintf (st, "                      TIMEPROMPTWAIT seconds.  A value of 0 for TIMEPROMPTWAIT\n");
fprintf (st, "                      will disable the clock setting prompt.\n");
fprint_reg_help (st, dptr);
return SCPE_OK;
}

const char *clk_description (DEVICE *dptr)
{
return "time of year clock";
}

static uint32 sim_byteswap32 (uint32 data)
{
uint8 *bdata = (uint8 *)&data;
uint8 tmp;

tmp = bdata[0];
bdata[0] = bdata[3];
bdata[3] = tmp;
tmp = bdata[1];
bdata[1] = bdata[2];
bdata[2] = tmp;
return data;
}

/* CLK attach */

t_stat clk_attach (UNIT *uptr, CONST char *cptr)
{
t_stat r;

uptr->flags = uptr->flags | (UNIT_ATTABLE | UNIT_BUFABLE);
memset (uptr->filebuf, 0, (size_t)uptr->capac);
r = attach_unit (uptr, cptr);
if (r != SCPE_OK)
    uptr->flags = uptr->flags & ~(UNIT_ATTABLE | UNIT_BUFABLE);
else {
    TOY *toy = (TOY *)uptr->filebuf;

    uptr->hwmark = (uint32) uptr->capac;
    if ((toy->toy_endian_plus2 < 2) || (toy->toy_endian_plus2 > 3))
        memset (uptr->filebuf, 0, (size_t)uptr->capac);
    else {
        if (toy->toy_endian_plus2 != sim_end + 2) {     /* wrong endian? */
            toy->toy_gmtbase = sim_byteswap32 (toy->toy_gmtbase);
            toy->toy_gmtbasemsec = sim_byteswap32 (toy->toy_gmtbasemsec);
            }
        }
    toy->toy_endian_plus2 = sim_end + 2;
    todr_resync ();
    }
return r;
}

/* CLK detach */

t_stat clk_detach (UNIT *uptr)
{
t_stat r;

r = detach_unit (uptr);
if ((uptr->flags & UNIT_ATT) == 0)
    uptr->flags = uptr->flags & ~(UNIT_ATTABLE | UNIT_BUFABLE);
return r;
}


/* Interval timer reset */

t_stat tmr_reset (DEVICE *dptr)
{
tmr_iccs = 0;
tmr_nicr = 0;
tmr_int = 0;
sim_cancel (&tmr_unit);                                 /* cancel timer */
return SCPE_OK;
}

const char *tmr_description (DEVICE *dptr)
{
return "interval timer";
}

/* TODR routines */

static const char *todr_fmt_vms_todr (int32 val)
{
static char buf[32];
uint32 uval = (uint32)val;

if (val < 0x10000000)
    sprintf (buf, "Not VMS Time: 0x%08X", uval);
else {
    int yday, hr, min, sec, msecs;

    uval -= 0x10000000;
    msecs = (uval % 100) * 10;
    uval /= 100;
    sec = uval % 60;
    uval /= 60;
    min = uval % 60;
    uval /= 60;
    hr = uval % 24;
    uval /= 24;
    yday = uval;
    sprintf (buf, "yday:%d %02d:%02d:%02d.%03d", yday, hr, min, sec, msecs);
    }    
return buf;
}

int32 todr_rd (void)
{
TOY *toy = (TOY *)clk_unit.filebuf;
struct timespec base, now, val;

sim_rtcn_get_time(&now, TMR_CLK);                       /* get curr time */
base.tv_sec = (time_t)toy->toy_gmtbase;
base.tv_nsec = toy->toy_gmtbasemsec * 1000000;
sim_timespec_diff (&val, &now, &base);                  /* val = now - base */
sim_debug (TMR_DB_TODR, &clk_dev, "todr_rd() - TODR=0x%X - %s\n", (int32)(val.tv_sec*100 + val.tv_nsec/10000000), todr_fmt_vms_todr ((int32)(val.tv_sec*100 + val.tv_nsec/10000000)));
return (int32)(val.tv_sec*100 + val.tv_nsec/10000000);  /* 100hz Clock Ticks */
}

void todr_wr (int32 data)
{
TOY *toy = (TOY *)clk_unit.filebuf;
struct timespec now, val, base;
time_t tbase;

/* Save the GMT time when set value was 0 to record the base for 
   future read operations in "battery backed-up" state */

sim_rtcn_get_time(&now, TMR_CLK);                       /* get curr time */
val.tv_sec = (time_t)((uint32)data) / 100;
val.tv_nsec = (((uint32)data) % 100) * 10000000;
sim_timespec_diff (&base, &now, &val);                  /* base = now - data */
toy->toy_gmtbase = (uint32)base.tv_sec;
tbase = (time_t)base.tv_sec;
toy->toy_gmtbasemsec = base.tv_nsec/1000000;
sim_debug (TMR_DB_TODR, &clk_dev, "todr_wr(0x%X) - %s - GMTBASE=%8.8s.%03d\n", data, todr_fmt_vms_todr (data), 11+ctime(&tbase), (int)(base.tv_nsec/1000000));
}

t_stat todr_resync (void)
{
TOY *toy = (TOY *)clk_unit.filebuf;

if (clk_unit.flags & UNIT_ATT) {                        /* Attached means behave like real VAX TODR */
    if (!toy->toy_gmtbase)                              /* Never set? */
        todr_wr (0);                                    /* Start ticking from 0 */
    }
else {                                                  /* Not-Attached means */
    uint32 base;                                        /* behave like simh VMS default */
    time_t curr;
    struct tm *ctm;
    struct timespec now;

    sim_rtcn_get_time(&now, TMR_CLK);                   /* get curr time */
    curr = (time_t)now.tv_sec;
    if (curr == (time_t) -1)                            /* error? */
        return SCPE_NOFNC;
    ctm = localtime (&curr);                            /* decompose */
    if (ctm == NULL)                                    /* error? */
        return SCPE_NOFNC;
    base = (((((ctm->tm_yday * 24) +                    /* sec since 1-Jan */
            ctm->tm_hour) * 60) +
            ctm->tm_min) * 60) +
            ctm->tm_sec;
    todr_wr ((base * 100) + 0x10000000 +                /* use VMS form */
             (int32)(now.tv_nsec / 10000000));
    }
return SCPE_OK;
}

/* Console write, txdb<11:8> != 0 (console unit) */

t_stat fl_wr_txdb (int32 data)
{
int32 sel = TXDB_GETSEL (data);                         /* get selection */

if (sel == TXDB_FCMD) {                                 /* floppy command? */
    fl_fnc = FL_GETFNC (data);                          /* get function */
    if (fl_state != FL_IDLE)                            /* cmd in prog? */
        switch (fl_fnc) {

        case FL_FNCCA:                                  /* cancel? */
            sim_cancel (&fl_unit);                      /* stop op */
            fl_state = FL_DONE;
            break;

        default:                                        /* all others */
            fl_protocol_error ();
            return SCPE_OK;
            }

        else switch (fl_fnc) {                          /* idle, case */

        case FL_FNCRS:                                  /* read status */
            fl_state = FL_READSTA;
            break;

        case FL_FNCCA:                                  /* cancel, nop */
            fl_state = FL_DONE;
            break;

        case FL_FNCRD: case FL_FNCWR:                   /* data xfer */
        case FL_FNCWD:
            fl_esr = 0;                                 /* clear errors */
            fl_ecode = 0;
            fl_bptr = 0;                                /* init buffer */
            fl_state = FL_RWDS;                         /* sector next */
            break;

        default:                                        /* all others */
            fl_protocol_error ();
            return SCPE_OK;
            }

    sim_activate (&fl_unit, fl_cwait);                  /* sched command */
    }                                                   /* end command */
else if (sel == TXDB_FDAT) {                            /* floppy data? */
    switch (fl_state) {                                 /* data */

        case FL_RWDS:                                   /* expecting sector */
            fl_sector = data & FL_M_SECTOR;
            fl_state = FL_RWDT;
            break;

        case FL_RWDT:                                   /* expecting track */
            fl_track = data & FL_M_TRACK;
            if (fl_fnc == FL_FNCRD)
                fl_state = FL_READ;
            else fl_state = FL_FILL;
            break;

        case FL_FILL:                                   /* expecting wr data */
            fl_buf[fl_bptr++] = data & BMASK;
            if (fl_bptr >= FL_NUMBY)
                fl_state = FL_WRITE;
            break;

        default:
            fl_protocol_error ();
            return SCPE_OK;
            }

    sim_activate (&fl_unit, fl_xwait);                  /* schedule xfer */
    }                                                   /* end else data */
else {
    sim_activate (&tto_unit, tto_unit.wait);            /* set up timeout */
    if (sel == TXDB_COMM) {                             /* read comm region? */
        data = data & COMM_MASK;                        /* byte to select */
        tti_buf = comm_region[data] | COMM_DATA;
        tti_csr = tti_csr | CSR_DONE;                   /* set input flag */
        if (tti_csr & CSR_IE)
            tti_int = 1;
        }
    else if (sel == TXDB_MISC) {                        /* misc function? */
        switch (data & MISC_MASK) {                     /* case on function */

        case MISC_CLWS:
            comm_region[COMM_WRMS] = 0;
            break;

        case MISC_CLCS:
            comm_region[COMM_CLDS] = 0;
            break;

        case MISC_SWDN:
            ABORT (STOP_SWDN);
            break;

        case MISC_BOOT:
            con_halt (0, 0);                            /* set up reboot */
            break;
            }
        }
    }
return SCPE_OK;
}

/* Unit service; the action to be taken depends on the transfer state:

   FL_IDLE              Should never get here
   FL_RWDS              Set TXCS<done> (driver sends sector, sets FL_RWDT)
   FL_RWDT              Set TXCS<done> (driver sends track, sets FL_READ/FL_FILL)
   FL_READ              Set TXCS<done>, schedule FL_READ1
   FL_READ1             Read sector, schedule FL_EMPTY
   FL_EMPTY             Copy data to RXDB, set RXCS<done>
                        if fl_bptr >= max, schedule completion, else continue
   FL_FILL              Set TXCS<done> (driver sends next byte, sets FL_WRITE)
   FL_WRITE             Set TXCS<done>, schedule FL_WRITE1
   FL_WRITE1            Write sector, schedule FL_DONE
   FL_DONE              Copy requested data to TXDB, set FL_IDLE
*/

t_stat fl_svc (UNIT *uptr)
{
int32 i, t;
uint32 da;
int8 *fbuf = (int8 *)uptr->filebuf;

switch (fl_state) {                                     /* case on state */

    case FL_IDLE:                                       /* idle */
        return SCPE_IERR;                               /* done */

    case FL_READ: case FL_WRITE:                        /* read, write */
        fl_state = fl_state + 1;                        /* set next state */
        t = abs (fl_track - uptr->TRACK);               /* # tracks to seek */
        if (t == 0)                                     /* minimum 1 */
            t = 1;
        sim_activate (uptr, fl_swait * t);              /* schedule seek */
                                                        /* fall thru, set flag */
    case FL_RWDS: case FL_RWDT: case FL_FILL:           /* rwds, rwdt, fill */
        tto_csr = tto_csr | CSR_DONE;                   /* set output done */
        if (tto_csr & CSR_IE)
            tto_int = 1;
        break;

    case FL_READ1:                                      /* read, seek done */
        if (fl_test_xfr (uptr, FALSE)) {                /* transfer ok? */
            da = CALC_DA (fl_track, fl_sector);         /* get disk address */
            for (i = 0; i < FL_NUMBY; i++)              /* copy sector to buf */
                fl_buf[i] = fbuf[da + i];
            tti_buf = fl_esr | FL_CDONE;                /* completion code */
            tti_csr = tti_csr | CSR_DONE;               /* set input flag */
            if (tti_csr & CSR_IE)
                tti_int = 1;      
            fl_state = FL_EMPTY;                        /* go empty */
            }
        else
            fl_state = FL_DONE;                        /* error? cmd done */
        sim_activate (uptr, fl_xwait);                  /* schedule next */
        break;

    case FL_EMPTY:                                      /* empty buffer */
        if ((tti_csr & CSR_DONE) == 0) {                /* prev data taken? */
            tti_buf = FL_CDATA | fl_buf[fl_bptr++];     /* get next byte */
            tti_csr = tti_csr | CSR_DONE;               /* set input flag */
            if (tti_csr & CSR_IE)
                tti_int = 1;
            if (fl_bptr >= FL_NUMBY) {                  /* buffer empty? */
                fl_state = FL_IDLE;                     /* cmd done */
                break;
                }
            }
        sim_activate (uptr, fl_xwait);                  /* schedule next */
        break;

    case FL_WRITE1:                                     /* write, seek done */
        if (fl_test_xfr (uptr, TRUE)) {                 /* transfer ok? */
            da = CALC_DA (fl_track, fl_sector);         /* get disk address */
            for (i = 0; i < FL_NUMBY; i++)              /* copy buf to sector */
                fbuf[da + i] = fl_buf[i];
            da = da + FL_NUMBY;
            if (da > uptr->hwmark)                      /* update hwmark */
                uptr->hwmark = da;
            }
        if (fl_fnc == FL_FNCWD)                         /* wrdel? set status */
            fl_esr |= FL_STADDA;
        fl_state = FL_DONE;                             /* command done */
        sim_activate (uptr, fl_xwait);                  /* schedule */
        break;

    case FL_DONE:                                       /* command done */
        if (tti_csr & CSR_DONE)                         /* input buf empty? */
            sim_activate (uptr, fl_xwait);              /* no, wait */
        else {                                          /* yes */
            tti_buf = fl_esr | FL_CDONE;                /* completion code */
            tti_csr = tti_csr | CSR_DONE;               /* set input flag */
            if (tti_csr & CSR_IE)
                tti_int = 1;
            fl_state = FL_IDLE;                         /* floppy idle */
            }
        break;    

    case FL_READSTA:                                    /* read status */
        if ((tti_csr & CSR_DONE) == 0) {                /* input buf empty? */
            tti_buf = fl_ecode;                         /* return err code */
            tti_csr = tti_csr | CSR_DONE;               /* set input flag */
            if (tti_csr & CSR_IE)
                tti_int = 1;
            fl_state = FL_DONE;                         /* command done */
            }
        sim_activate (uptr, fl_xwait);
        break;
        }
return SCPE_OK;
}

/* Test for data transfer okay */

t_bool fl_test_xfr (UNIT *uptr, t_bool wr)
{
if ((uptr->flags & UNIT_BUF) == 0)                      /* not buffered? */
    fl_ecode = 0110;
else if (fl_track >= FL_NUMTR)                          /* bad track? */
    fl_ecode = 0040;                                    /* done, error */
else if ((fl_sector == 0) || (fl_sector > FL_NUMSC))    /* bad sect? */
    fl_ecode = 0070;                                    /* done, error */
else if (wr && (uptr->flags & UNIT_WPRT))               /* write and locked? */
    fl_ecode = 0100;                                    /* done, error */
else {
    uptr->TRACK = fl_track;                             /* now on track */
    return TRUE;
    }
fl_esr = fl_esr | FL_STAERR;                            /* set error */
return FALSE;
}

/* Set protocol error */

void fl_protocol_error (void)
{
if ((tto_csr & CSR_DONE) == 0) {                        /* output busy? */
    tto_csr = tto_csr | CSR_DONE;                       /* set done */
    if (tto_csr & CSR_IE)
        tto_int = 1;
    }
if ((tti_csr & CSR_DONE) == 0) {                        /* input idle? */
    tti_csr = tti_csr | CSR_DONE;                       /* set done */
    if (tti_csr & CSR_IE)
        tti_int = 1;
    }
tti_buf = FL_CPROT;                                     /* status */
fl_state = FL_IDLE;                                     /* floppy idle */
}

/* Reset */

t_stat fl_reset (DEVICE *dptr)
{
uint32 i;
extern int32 sys_model;

fl_esr = FL_STAINC;
fl_ecode = 0;                                           /* clear error */
fl_sector = 0;                                          /* clear addr */
fl_track = 0;
fl_state = FL_IDLE;                                     /* ctrl idle */
fl_bptr = 0;
sim_cancel (&fl_unit);                                  /* cancel drive */
fl_unit.TRACK = 0;
for (i = 0; i < COMM_LNT; i++)
    comm_region[i] = 0;
if (sys_model) {    /* 785 */
    comm_region[COMM_WCSS_785] = VER_WCSS_785;
    comm_region[COMM_WCSP_785] = VER_WCSP_785;
    comm_region[COMM_MTCH_785] = VER_MTCH_785;
    comm_region[COMM_PCSV] = VER_PCS_785;
    }
else {              /* 780 */
    comm_region[COMM_FPLV] = VER_FPLA;
    comm_region[COMM_PCSV] = VER_PCS;
    comm_region[COMM_WCSV] = VER_WCSP;
    comm_region[COMM_WCSS] = VER_WCSS;
    }
comm_region[COMM_GH] = 1;
return SCPE_OK;
}

const char *fl_description (DEVICE *dptr)
{
return "console floppy";
}