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#106369 07/06/16 12:32 AM
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In esq5505.cpp a file is mentioned called es5700.pdf containing PLA equations. Can't find that file anywhere, anybody have it?

Also interested in EPS16+ schematics (only EPS and ASR-10 schems are publicly available).

Was there any documentation on the auxiliary microprocessors such as the display and keyboard controllers?

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You can get that and a few other things here:
https://web.archive.org/web/20141129033148/http://raidenii.net/files/datasheets/apu/

EPS16+ schematics don't exist anywhere I have access to. SD-1 ones do but I lost my copy, I'd need to email the guy who gave them to me smile Can you point me to the EPS and ASR-10 ones?

The display/keyboard controllers (they're usually the same chip) are either a 6500 (a 6502-based micro controller) or a 68HC11. They're not documented outside of the schematics showing which GPIOs on them are connected where.

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Ok, thanks! There exists a scan of the EPS16+ Service Manual, but it is pretty useless and contains no schematics.

I read the original EPS used a NEC 7538 for the display, a 4Kb PROM 4-bit 7500 micro with a built in high voltage VFD driver, (many of the related Ensoniqs also uses VFDs). There exists a datasheet for a uPD7533 in the same family that possibly has the same instruction set (NEC 7500 Set A). Some other 7500 series datasheets lists opcodes, but so far I've found only for Instruction Set B types. There are old data books from NEC that might contain more, but I'm calling it a day.

This stuff is probably not even relevant for MAME because it can be emulated perfectly on a higher level (and already is), I'm just leaving it here for internet posterity, because I spent a lot of time tracking down the information and it certainly ain't relevant for anything else.

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The 68HC11 code would actually be interesting to see, because the infamous Ensoniq ERROR 144 was said (by Ensoniq themselves) to come from MIDI and keyboard data using up all available "system buffers". It seems very strange that a multi-megabyte 68k would run out of system buffers from MIDI. Perhaps there is a bug in the keyboard processor code.

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We have a dump of the 68HC705 display/keypad controller from an MR-Rack in esqmr.cpp.

And the 68k isn't multi-megabyte; in the non-sampling versions of the family there's usually only 64 or 128KB RAM total, so space is tight.

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Great, I'll have a look! Perhaps one day I'll dump my own Ensoniqs and upload.

You are right about the RAM of course, but if i remember correctly the samplers are the ones that crashes the most, by far. I have seen my fair share of ERROR 144.

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Originally Posted By Squash
This stuff is probably not even relevant for MAME because it can be emulated perfectly on a higher level (and already is)


Quite the contrary, if it's possible to emulate something at a lower level, MAME generally tries to.


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