This change signficantly improves header hygiene in the 3B2 project by
moving global symbols out of 3b2_defs.h and into the appropriate
individual module header files.
Each compilation unit now includes:
- its appropriate matching .h file
- any other .h files necessary for linting and compilation
Each header file in turn includes 3b2_defs.h, which contains truly
global symbols, and which pulls in sim_defs.h and exports global
devices.
This change introduces initial support for the AT&T 3B2 Rev 3 platform, based
around the WE32200 CPU with up to 64MB of RAM and SCSI disk and tape support.
This simulator is experimental and not yet supported. It will not be built by
default, but can be built with:
make 3b2-600
Or by using the 3B2-600 Windows Visual Studio project.
Refactor in preparation for the addition of a Rev 3 simulator for the
3B2/1000 system.
This change also includes a full cleanup of the rat's-nest of includes
and externs that plagued the 3B2 simulator and made it difficult to
understand and maintain. Headers are now required in the following
order:
compilation unit -> "3b2_defs.h" -> {... dependencies ...}
Finally, HELP has been added to the CPU device.
This change is a major refactor of how DMA and the DUART interact.
DMA implementation can now be overridden by individual devices that
require DMA. Disk and Floppy both continue to use a generic DMA
implementation, but the DUART code replaces the generic DMA with its
own implementation that correctly rate-limits TX. Among other things,
this allows the simulator to work correctly with real serial
terminals. This functionality has been tested on an AT&T 5620 "Blit"
terminal, which can run the 'layers' windowing software from the
simulator.
