Subversion Repositories vtach

This is the VTACH simulator of the CARDIAC computer.

You can read more at:

http://www.drdobbs.com/embedded-systems/cardiac-to-fpga/240155599

http://www.drdobbs.com/embedded-systems/paper-to-fpga/240155922

http://www.drdobbs.com/embedded-systems/expanding-vtach/240155198

http://www.drdobbs.com/embedded-systems/troubleshooting-verilog/240154701

http://www.drdobbs.com/embedded-systems/the-cpu-crawl/240154406?

http://www.drdobbs.com/embedded-systems/the-heart-of-a-cpu/240153772

More info on CARDIAC

http://en.wikipedia.org/wiki/CARDboard_Illustrative_Aid_to_Computation

You can find a simple cross assembler in the asm directory.

To assemble code in test asm:

axasm -p cardiac -x -o test.coe test.asm

Then set the block ram to initialize from test.coe (in the

block memory wizard) and rebuild.

Expanded opcodes:

480 - Read toggle switches to accumulator

490, 408, 409 - Read pushbutton to accumulator (-1 for pressed, 1 for not pressed)

Changed opcodes:

INP - Read toggle switches (up to you to obey BCD and yes you can't enter >99)

OUT - Output to the LED display

Author - Al Williams al.williams@awce.com

If you use this in an educational setting, I'd enjoy hearing about it.

Actually, if you use this at all, I'd probably enjoy hearing about it :-)