> got a cable loopback attached.
>
> figured out the problem is actually my VINT- IRQ (too short)
so I modified my model1-connector and added a jumper to select VINT- src.
The "IOR-" signal of the ISA-bus actually is too short for the Z80 to recognize.
I used the A15 line to "control" the VINT- line. every 17ms I write 'address && 0x7FFF' follow by a write 'address || 0x8000'.
these are long enough for the z80 (yeah), but as it turns out, to "slow" to keep the connection alive. (i can see the TOSLINK turning on and off with each irq)
As for now I'll try to find other (reliable) signals - most likely the VGAs (negative!) VSYNC.
*EDIT*
just tried the VGA VSYNC and it seems to work well enough.
*EDIT2*
Consider it "working". 8MHz Host-Clock (32M / 4), 2MHz Serial-Clock (8/4)
Shared Memory "setup" with EPR-15112 (Model1 - Virtua Racing / WingWar)
0x000 to 0x00F - status area
0x010 to 0x1D3 - local tx area
0x1D4 to 0x397 - rx area (node 1)
0x398 to 0x55B - rx area (node 2)
0x55C to 0x71F - rx area (node 3)
0x720 to 0x8E3 - rx area (node 4)
0x8E4 to 0xAA7 - rx area (node 5)
0xAA8 to 0xC6B - rx area (node 6)
0xC6C to 0xE2F - rx area (node 7)
0xE30 to 0xFF3 - rx area (node 
0xFF4 to 0xFFF - unused
this means 452 bytes "per node", up to 8 nodes.
(relay mode does NOT count a node).
I do all that stuff even without a Joystick 
Soft-15kHz, cabMAME, For Amusement Only e.V.
Edited by SailorSat (10/19/14 03:39 PM)
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Re: "Interfacing" the model1 comm board
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