KEK/tm-11.cpp

146 lines
3.3 KiB
C++

// (C) 2018-2023 by Folkert van Heusden
// Released under MIT license
#include <errno.h>
#include <string.h>
#include "tm-11.h"
#include "gen.h"
#include "log.h"
#include "memory.h"
#include "utils.h"
tm_11::tm_11(const std::string & file, memory *const m) : m(m)
{
fh = fopen(file.c_str(), "rb");
reset();
}
tm_11::~tm_11()
{
fclose(fh);
}
void tm_11::reset()
{
memset(registers, 0x00, sizeof registers );
memset(xfer_buffer, 0x00, sizeof xfer_buffer);
offset = 0;
}
uint8_t tm_11::readByte(const uint16_t addr)
{
uint16_t v = readWord(addr & ~1);
if (addr & 1)
return v >> 8;
return v;
}
uint16_t tm_11::readWord(const uint16_t addr)
{
const int reg = (addr - TM_11_BASE) / 2;
uint16_t vtemp = registers[reg];
if (addr == TM_11_MTS) {
setBit(vtemp, 15, false); // ILC
setBit(vtemp, 14, false); // EOC
setBit(vtemp, 13, false); // CRE
setBit(vtemp, 12, false); // PAE
setBit(vtemp, 11, false); // BGL
setBit(vtemp, 10, false); // EOT
setBit(vtemp, 9, false); // RLE
setBit(vtemp, 8, false); // BTE
setBit(vtemp, 7, false); // NXM
setBit(vtemp, 6, true); // SELR
setBit(vtemp, 5, false); // BOT - beginning of tape
setBit(vtemp, 4, false); // 7CH
setBit(vtemp, 3, false); // SDWN
setBit(vtemp, 2, false); // WRL - write lock
setBit(vtemp, 1, false); // RWS
setBit(vtemp, 0, true); // TUR - tape unit ready
}
else if (addr == TM_11_MTC) {
registers[reg] ^= 1 << 7; // CU RDY
}
else if (addr == TM_11_MTBRC) { // record length
vtemp = 0;
}
DOLOG(debug, false, "TM-11 read addr %o: %o", addr, vtemp);
return vtemp;
}
void tm_11::writeByte(const uint16_t addr, const uint8_t v)
{
uint16_t vtemp = registers[(addr - TM_11_BASE) / 2];
if (addr & 1) {
vtemp &= ~0xff00;
vtemp |= v << 8;
}
else {
vtemp &= ~0x00ff;
vtemp |= v;
}
writeWord(addr, vtemp);
}
void tm_11::writeWord(const uint16_t addr, uint16_t v)
{
DOLOG(debug, false, "TM-11 write %o: %o", addr, v);
if (addr == TM_11_MTC) {
if (v & 1) { // GO
const int func = (v >> 1) & 7; // FUNCTION
const int reclen = 512;
DOLOG(debug, false, "invoke %d", func);
if (func == 0) { // off-line
v = 128; // TODO set error if error
}
else if (func == 1) { // read
DOLOG(debug, false, "reading %d bytes from offset %d", reclen, offset);
if (fread(xfer_buffer, 1, reclen, fh) != reclen)
DOLOG(info, true, "failed: %s", strerror(errno));
for(int i=0; i<reclen; i++)
m -> writeByte(registers[(TM_11_MTCMA - TM_11_BASE) / 2] + i, xfer_buffer[i]);
offset += reclen;
v = 128; // TODO set error if error
}
else if (func == 2) { // write
for(int i=0; i<reclen; i++)
xfer_buffer[i] = m -> readByte(registers[(TM_11_MTCMA - TM_11_BASE) / 2] + i);
fwrite(xfer_buffer, 1, reclen, fh);
offset += reclen;
v = 128; // TODO
}
else if (func == 4) { // space forward
offset += reclen;
v = 128; // TODO
}
else if (func == 5) { // space backward
if (offset >= reclen)
offset -= reclen;
v = 128; // TODO
}
else if (func == 7) { // rewind
offset = 0;
v = 128; // TODO set error if error
}
}
}
else if (addr == TM_11_MTCMA) {
v &= ~1;
DOLOG(debug, false, "Set DMA address to %o", v);
}
DOLOG(debug, false, "set register %o to %o", addr, v);
registers[(addr - TM_11_BASE) / 2] = v;
}