68kMLA Classic Interface
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| Click here to select a new forum. | | SE/30 MLB with samasimac + discordant slow chimes | Posted by: elemenoh on 2020-05-22 16:22:47
This one is pretty interesting. It boots with a typical samasimac screen, but the chimes are all over the place. I guess I have an accidentally circuit-bent SE/30 synthesizer!
I've already replaced UD8, UE8 and UF8. Known-working ROM and RAM is installed. This is a different board than the other one I've been posting about recently. I'll get to testing stuff, but if you have recommendations for where to focus please let me know.
| Posted by: IlikeTech on 2020-05-25 18:41:25
Almost seems like it's hanging while reading the ROM. Bad contact in the ram sockets? Maybe bad sound chips?
| Posted by: techknight on 2020-05-26 06:08:14
You should grab the schematics, and verify all the connections for Address, Data, and control lines between the ASC, and the rest of the system. Preferably back at the GLUE chip, ROM SIMM, etc...
Usually the data lines/address lines break at the ASC, and sometimes its broken at the SCSI and SCC as well. So verify it all the way back at the glu logic, and ROM SIMM.
Some of the control lines only go to the glue logic chip. so check those too, ive seen them open.
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