I am reverse engineering a old circuit board, probably from the late seventies (specifically an Enteron sk-1600-a industrial controller), And I am having trouble finding data sheets.

Firstly I am guessing that Motorola has sold off the divisions making many of the chips on this board and that they are now sold under some other name (ie Motorola moc3021 is obviously from how it is used on the board an opto-isolated triac driver and Fairchild moc3021 fits and has the same pinout, similarly their uln2003a could now be made by texas instruments although using a darlington bridge with flyback diode seems like overkill for driving the moc3021, and the mc14020b could fit the counter by on semiconductor as it is near the clock crystal).

Secondly I am guessing that some have gone the way of the dodo like the ami 8616 (looks like an eight bit processor) and the ami 8424 (probably a parallel io chip).

If anyone can partially endorse the modern data sheets (these parts are mostly compatible with their predecessors) or even better has the right data sheets, It would certainly be appreciated.

  • \$\begingroup\$ I think Motorola CMOS logic with MC14xxx part numbers was equivalent to RCA CMOS CD4xxx. \$\endgroup\$ Apr 4 '16 at 2:54
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    \$\begingroup\$ I bet the '8616' and '8424' are actually date codes. What other markings do the AMI chips have, and how many pins? \$\endgroup\$ Apr 4 '16 at 6:13
  • \$\begingroup\$ @BruceAbbott, the other number on the 8616 is 56802p. the 8424 is also marked s6821p. they are both wide 40 pin dpi packages (same size as a zilog z80 or intel 8080) \$\endgroup\$
    – hildred
    Apr 4 '16 at 7:34
  • \$\begingroup\$ google.co.uk/… \$\endgroup\$
    – Andy aka
    Apr 4 '16 at 11:00
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    \$\begingroup\$ I'd guess that you have a 6802 processor and a 6821 parallel interface adapter. the '5' you have before 6802 is actually "S". \$\endgroup\$
    – brhans
    Apr 4 '16 at 12:49

Motorola 6821 is here but I don't think the Motorola DSP56xxx series was going in the 70s.


As pointed out in a comment, the initial markings you were looking at are date codes (24th week of 1984 & 16th week of 1986).

The actual part numbers you have are S6821P and S6802P (not 56802P).

The S6821P is more generically known as a 6821 Parallel Interface Adapter, and the S6802P is a 6802 8-bit Microprocessor.

The S prefix seems to be a standard for the manufacturer which made those specific parts you have, as the original Motorolla parts would start with MC.


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