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RE: [N8VEM-S100:4766] 8080 board, Firmware and break

Hi Guys,

I have been able to get CP/M 2.2 booting from the SD-Memory card.  Please find the JAIR-Firmware V1.zip file on the wiki page.

It will boot CP/M 2.2 and give the "a>" prompt.  (I thought it would be a capital A, but it's not.)

It does not change to Drive B (haven't tested C or D with any serious investigations).
When trying to change to drive B, CP/M attempts to access Track 0xFF Sector 0, which are not valid.  Track should be between 0 and 76 (77 tracks in all) and Sector# should be between 1 and 26.  I'm not sure how or where it's coded in the drive parameter table.  Perhaps these are the previous values that just haven't been initialized properly?  I will need to go deep into CP/M territory to resolve this issue, but don't want to keep you waiting for some sort of firmware.

Further, I have updated the schematic with the latest changes and updated the Manual with all the ECO changes (see wiki page).
There are 3 ECO's required:
-Jumper for the SD card
-Jumper for the disconnected IC-H7 (8T97) pin 15
-Change RP2 from 4.7K to 47K  (to solve issues with 16550 UART and 82C50 UART).

I must now unplug this project for 5 weeks.  I am exhibiting a COSMAC ELF collection at VCF-MW in Chicago and have only 5 weeks to finish my preparations for this. 

Mr. Jack Rubin, I have your board packed with my RCA STUDIO II, see you at the show!

Mr. Matthew Turner, Thank you again for the loan of your Super ELF.  I will get to work on it in a priority sequence (it's about #7 on my list).

Josh Bensadon