28 May
2013
28 May
'13
2:47 p.m.
Jos Dreesen wrote:
The spare parts box that was part of a tek4052 deal
has several
Tektronix
specific 40 pins DIL, date around 1973
These are
156-0235-00 C8684
156-0238-00 C1840
156-0236-00 C1841
156-0243-00 C1842
also a MOS MCS1020
Anyone know what these were from ( not the 4052), maybe a tek 31 ?
The C codes are AMI "Customer Developed Custom" chips. The code
identifies the mask set used to make the chip.
The 156- numbers are the internal Tektronix part number.
All of these C-code devices are indeed from the ALU of a Tek 21/31
calculator.
The microcoded ALU in the Tek 21/31 calculators was designed by
Tektronix, but farmed out for manufacture to AMI.
I have tried both Tektronix and AMI to get pinouts/functionalty
information about these chips (along with the others in the set) with
no luck. Tektronix says it has no records of them, and AMI says they
will not release any information relating to customer-designed custom
devices due to intellectual property laws.
There were 13 chips in the set.
Not sure about the MOS MCS1020 chip..don't have my Tek 21/31 Service
Manual with me, nor does it exist in digital form that I can refer to.
It doesn't sound familiar to me relating to the Tek 21/31, though.
Rick Bensene
The Old Calculator Museum
http://oldcalculatormuseum.com
http://oldcalculatormuseum.com/tek31.html