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68K BUS DIAGNOSTICS BOARD

Posted: 24 Jun 2024 19:59
by exxos
0289.jpg

This board hardwires all the address bus lines which can be configured using jumper links for the first few addresses to allow verification of the first several ROM data accesses.

The board is useful for verifying the functionality of the address and data bus, ensuring the connections to the ROM and GLUE are sufficient to complete the initial bus cycles of the system. It also checks if the reset signal and clock are operational.

To use the sniffer, remove the 68K CPU from your motherboard and insert this bus sniffer board in its place. During reset, all the low LEDs will light up, indicating all zeros. After reset, observe the patterns displayed, assuming you are using TOS104.

The data is shown on a bank of LEDs, with both HI and LO LEDs lighting up. Additionally, two LEDs on the far left of the board will light up if the 8MHz clock is functioning.


STORE
https://www.exxosforum.co.uk/atari/store2/#0289

PREVIOUS DIAGNOSTIC PAGE
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NEW HOMEPAGE
https://exxosforum.co.uk/atari/last/68KBUSSNIFFER/

Re: 68K BUS DIAGNOSTICS BOARD

Posted: 25 Jun 2024 11:45
by Badwolf
Ooo muchos blinkenlights!

Nice design & I imagine very useful in a completely dead / suspected damaged trace situation.

:2k2:

BW

Re: 68K BUS DIAGNOSTICS BOARD

Posted: 26 Jun 2024 21:11
by exxos
Webpage now done.

https://exxosforum.co.uk/atari/last/68KBUSSNIFFER/

As people may have different TOS versions, I've done a script which will allow you to upload your TOS image and the script will output the binary sequences for you. I've only put TOS104 on the site as I assume that's what most people will be running.

Thanks also to @ijor for figuring out why it was only working with the first few addresses :lol: :roll:

Re: 68K BUS DIAGNOSTICS BOARD

Posted: 27 Jun 2024 01:59
by atari030
That's absolutely brilliant. :cheers: