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The MOTOROLA VME, EXORciser and MicroModules Thread (6800, 6809, 68K)

I've removed one of the 2 pin devices, clearly it is a 10n cap. Devil to get out due to the heat sinking power planes.
Can post pictures tomorrow.
 
It looks like after 40 years the EEPROMS have lost data. There is no activity on the bus.
 
Should get hold of a programmer early next week. I have a couple of stepper controllers that may need dumping also.
 
The EPROMs are Texas TMS2532, different pinout to 2732s, so I can't read - unless there is an adapter. I suspect the bunch of jumpers near the 24DIL sockets are for configuration.
 
Only a few pins to swap.
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2532 EPROM uses & adapter for TL866

So I acquired a 2532>2732 adapter from a very nice Guy, Dave Stevenson from the UK who is offering them for sale on his hobby website: http://www.primrosebank.net/computers/pet/projects/roms/pet_roms.htmI didn't want to make an adapter from scratch, butI got his bare PCB, and soldered my own s...
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Found enough parts to cobble up an adapter. I've dumped two chips, will do others tomorrow - too tired now.
Read at 5V and verified at 5, 4.75 and 4.5.

Some of the AM2732A I tested today started to show about a dozen fails below 5V verify, these were out of a similar age Apple I/O board
 

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Found these boards, still sealed. No idea what they are, or who made them for what purpose.

The 2 boards look like PSUs and the 3 pack, some kind of logic board.

Any ideas and/or useful to anyone?

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geoff7 said:
Found enough parts to cobble up an adapter. I've dumped two chips, will do others tomorrow - too tired now.
Read at 5V and verified at 5, 4.75 and 4.5.

Some of the AM2732A I tested today started to show about a dozen fails below 5V verify, these were out of a similar age Apple I/O board
Click to expand...
With a great deal of assistance from Marc, the M68VECPU100 system is now running. Remarkably the Intel 2532 EPROMs have survived over 40 years!
This must be one of the earliest Motorola boards , built in 1983. Other than the processor and I/O all the chips are 74S or 74LS glue logic.

I'm currently building a cage to hold the boards.
 

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I've discovered that the Bug code will support a Centronics printer with a couple of buffers added to the PIA ports. I've used the correct Centronics connector.
There is one conundrum, it works with a HP Laserjet but not with a Epson FX dot matrix printer, there is no Acknowledge from the Strobe signal. Both printers work on a PC. The only difference seems to be the PC strobe is 1 us and the VME strobe is 5 us - but both are within spec. I've used tristate buffers so they can be disable to use the ports for digital I/O
 

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It's been a long time since I looked at the centronics interface but I would guess one device uses ACK and the other uses BUSY for handshake.
Got a scope?
 
When the FX is working it returns ACK low 8 us after strobe for 4us. No ACK when driven from the VME. Could be BUSY problem.
The Centronics schematic is from the VME101 manual.
 
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