BUS error handling

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tuxie
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BUS error handling

Post by tuxie » Sat Mar 17, 2018 4:23 pm

didnt find any Infos... but maybe someone can explain me..

how does the ST handle the Bus error.

Read in the Atari Profibuch that when the cpu access a memory address and the repsonible address does not answer with a dtack signal then after 64 cycles a bus error occurs.

thx

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exxos
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Re: BUS error handling

Post by exxos » Sat Mar 17, 2018 5:06 pm

AFAIK that is pretty much it. GLUE watches for DTACK access, if doesn't see DTACK reply it will set BERR to the CPU... Likely 68000 doc will explain what happens then.
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tuxie
Posts: 58
Joined: Thu Aug 24, 2017 11:51 am

Re: BUS error handling

Post by tuxie » Sat Mar 17, 2018 5:08 pm

these is what i found too... but what happens after the buserror occurs ? The cpu has two possibilitys
1. Redo it again
2. Handle it like a autovector interrupt

tuxie
Posts: 58
Joined: Thu Aug 24, 2017 11:51 am

Re: BUS error handling

Post by tuxie » Sat Mar 17, 2018 5:14 pm

found it in the Service Manuel

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