osiweb.org

Board came up nicely with the TTL port, but I couldn't get the RS232 running. I haven't had time to scope it out.

What gender did you use for the DB9 connector?

- Gary

I used a Male DB9 in my implementation. The design was copied from Grant Searle's schematic, but I haven't actually built it. I am still waiting for a pcb from Charles. I will ask him if he can test his board.

Steve

Yup, that's probably my issue (I used a female DB-9).

I'll try and swap in out and see.

Thanks again for a very nice PCB design!

- Gary

Good luck. Let me know how it goes!

Steve

Charles found my error. Looks like I messed up the Tx and Rx going to the DB9. I used T2OUT (pin 7) and R2IN (pin 8). You'll need to change these to T1OUT and R1IN (pins 14 and 13). Sorry about that.

Steve

I bet you can just jumper 8 to 13 and 10 to 11.

If you do get a second to fix the gerber files let me know. I can order a new set shortly (I have a few other boards to order) and confirm all is ok!

It's a very cute board btw. I have some spare of the current board (which works fine with a TTL==USB adapter) if anyone would like one (and I can program the 27256 ROM for folks).

- Gary

I will update the board in the next day or two.

Steve

No rush, thanks!

Jumpering 8 to 13 and 10-11 does let the serial port work fine.

Released V1.02 with Tx and Rx fixes and cleaned up a bunch of little track issues. Updated Gerbers are available.

Steve

I hand built one of these using point to point wiring back in 2010 or so. I modified the chip select logic to fill in the two gaps in the memory map with ROM. I was able to get it working with Tom Pitman's TINY BASIC, Lee Davidson's EhBASIC and. of course, the UK-101 version of MS BASIC.
The two 20-pin chips on the top of the board are a parallel I/O port I added on.