I made a modification to the programmer board and finally
got around to building and testing it. All I did was add a 128Kx8 SPI EPROM for
program storage. The original programmer worked fine but the Z80 board, since
it has no ROM, had to have a program loaded each time it was turned on. With
the EPROM on board, depending on the configuration switches, the Z80 will start
up as before (Manual mode), or automatically load a RAM image and start
running. There is a second switch to indicate which of the 2 images to load. I
also ended up putting it into a box with a 5V power supply to make it a bit
easier to work with when away from the lab. The Z80 board is mounted on top
with the programmer mounted inside.
The box used was from a different project so that is why the location of the AC input is not exactly where I would like it. The front panel switches are as I described. The top has the reset button along with the programmer status LED. Not pictured is the USB connector (on the left side) for the serial port to the PIC on the programmer to communicate with the programmer software.
The programmer software was also modified to allow
programming the EPROM or the Z80.
No comments:
Post a Comment