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Re: [N8VEM-S100:3592] Re: Run of Dual CF-Card/Hard Disk IDE S-100 Boards

A bit more on the Dual IDE card problem I'm having.

The single IDE card version of MYIDE will stay with whatever card is previously selected. Eg, if I use the monitor to output 01 to 034H card "B"/Left will be selected and MYIDE will read/write/format to that card. If I use the monitor to output 00 to 034H card "A"/Right will be selected and MYIDE will read/write/format to the "A" card.

So, I took the single IDE card version of MYIDE and patched in an "A" and "B" option that will just output to the port. Interestingly if I start up the program with the "A" card selected all works well with "A". If I then select "B" and it will switch cards to "B" and work fine. Unfortunately I can't re-select "A" without going back to the monitor. If I exit CP/M, I can re-select "A" with the monitor.

I think the problem is a software issue, but I haven't had any luck fixing it <yet>. I've tried adding code to reselect the 034H port as an output, and called the IDEinit routine twice, add delays - all without any success:

    CALL    IDEinit
    MVI    A,80        ;Set ports for output
    OUT    IDEportCtrl
    MVI    B,20H
    DCR    B
    JNZ    DSELECTA    ;Delay
    MVI    A,0        ;Select Drive A:
    OUT    IDEDrive
    CALL    IDEinit

Any ideas appreciated!

- Gary

On 5/10/2014 8:34 AM, geka...@gmail.com wrote:
David -

After MYIDE initializes the "Select B" led is lit, and the display shows 00:00:01 I'm under the impression that the left slot (facing the front of the board) is "A".
I've used the schematic linked to on the John's site.
My CPU is an ADC SuperSIx set at 4mhz. There shouldn't be any I/O conflicts with the 30H range, and the drives will select correctly when manually outputting to 034H with the monitor.

I have one of the earlier single IDE cards which seems to work properly using the same IDE==>CF adapter and CF card. Obviously I can't test the drive switching with that setup. I did have to play around with the 7404 as noted on John's page - and ended up using an oddball 74PC04 in that setup.

Any suggestions are very appreciated. I tried paralleling a second 680 ohm SIP with no improvement. I don't currently have a 74S03 here, but have tried 7403, 74LS03, 7438 and 74LS38.

- Gary