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A7800 log files


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#1 Heaven/TQA OFFLINE  

Heaven/TQA

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Posted Wed Apr 17, 2019 11:56 PM

Can someone explain me those output?

I am on a standard 128kb 7 banks SGR cart...

How can the CPU do such things?

And what are undefined Maria reads?

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Edited by Heaven/TQA, Thu Apr 18, 2019 2:01 AM.


#2 Heaven/TQA OFFLINE  

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Posted Thu Apr 18, 2019 4:44 AM

how can A7800 read from memory with a LSR? don't get that... same with unmapped memory reads.



#3 RevEng OFFLINE  

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Posted Thu Apr 18, 2019 9:45 AM

Undefined MARIA reads means you are reading from a write-only register.

As far as register opcodes causing a read, this is inherited from MAME... I believe this comes into play if you trap on a value less than 256. The emulator traps on the opcode (or argument) getting loaded onto the bus for the 6502.

I haven't found a convenient workaround yet.

#4 Heaven/TQA OFFLINE  

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Posted Thu Apr 18, 2019 11:17 AM

Ok.... can I trust mame/a7800 or ignore?

#5 RevEng OFFLINE  

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Posted Thu Apr 18, 2019 11:36 AM

About the undefined reads? Yes. That comes from the Maria driver.




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