40-pin controller IC identity?

It's a wild guess, but that's an old National Semi logo. I'd check the COP8 family, because it's low cost, e.g. COP888CG (comes in a 40 DIP).

Frank

National MM9224.

Looks like a custom mask-programmed micro. It's a Nat-Semi of some variety, but I'm not familiar enough with their range of microcontrollers to make an intelligent suggestion as to which one. If you can find the right 'family' on their website, you should at least then be able to identify clocks, power & I/O pins, if that's any help to you. You might also try contacting a support person there & see if they have any ideas:

Nice work, Meat. Made obsolete in '97, apparently:

Obsolete Part Alternate Part or Supplier Source Last Time Buy Date Distributor

1. MM9224-VUL NONE NONE 12/31/97 N/A

Almost certainly not. 9224 is the date code.

I'd guess it to be a COP8 8-bit CMOS microcontroller (mask programmed). Clock should be on pins 6 and 7, which it looks to be (axial-lead ceramic caps, 1/8W bias resistor and 2-pin resonator in the photo). You should see a clock on pin 6.

/Reset should be on pin 34 (but it looks to be tied to another pin).

Vcc should be on 8 and GND should be on 33.

Eg. COP688CL/COP988CL

Best regards, Spehro Pefhany

or could this be a SC\MP version of NatSemi. discontinued see heavier traces on 20 and 40 rw

I thought about SC/MP, but '92 sounded a bit late. The SC/MP was out in the late '70s. I wouldn't have thought it survived that long.

On 17 Mar 2007 08:56:38 -0700, snipped-for-privacy@gmail.com put finger to keyboard and composed:

AFAICT, the date code of Q15 is 9920 and for the relays it is 9807. Would it make sense for a manufacturer to use old mask ROMmed stock in a new design?

- Franc Zabkar

On Fri, 16 Mar 2007 23:15:35 -0700, SparkyGuy put finger to keyboard and composed:

Identify the other ICs and work backwards.

AFAICT, the date codes for Q15 and for the relays suggest that it was built as late as 9920. Is this confirmed by the date codes on the other chips?

- Franc Zabkar

On Sat, 17 Mar 2007 12:40:13 -0500, Spehro Pefhany put finger to keyboard and composed:

A search of Google Groups suggests that the 16-pin chip may be a ULN2003 which would confirm that the uP has 8-bit IO ports. Tracing the ULN2003's inputs back to the uP would identify the uP's IO pins.

- Franc Zabkar

early

My Google skillz Rock!

Be quiet, you've ruined my moment of stardom!.

Something that's mask programmed, you don't want to buy in small quantities. Hence so long as the design is still viable, you don't want to change things until you absolutely have to (such as running out of that mask programmed device, or something else is just no longer available).

Michael

Yes. Where I work, we have "masked" [actually they are OTP, but they are factory-programmed and sold as "masked"] COP micros dating back at least five years. We'll still be making those products five or six years from now, and those chips were last time buy two years ago. Less expense and trouble to do a last time buy for the product's expected lifespan than to port everything to a new micro.

Were they still making the SC/MP in '92? The last time I saw an SC/MP was in 1980!

You'll have to wait until 2008 when the picture becomes available.

The 8-pin says "3-544" and is probably a 73-544 clock gen. The resonator is right there between it and the 40 pin'r.

I've owned since about mid '98. The relays were replaced maybe ~'99. Don't think the transistor was replaced, but might be.

On Sat, 17 Mar 2007 23:41:04 -0700, SparkyGuy put finger to keyboard and composed:

Could it be a house-numbered serial EEPROM, eg 93Cxx ???

According to the datasheet for the COP8 ...

port pin# function ---------------------------------------------- G4 3 SO (MICROWIRE Serial Data Output) G5 4 SK (MICROWIRE Serial Clock) G6 5 SI (MICROWIRE Serial Data Input)

I think the DIP-14 and DIP-16 IO chips should give you a clue as to the uC's port layout. I'm betting that one chip drives various external relays while the other accepts inputs from sensors.

- Franc Zabkar