Published 8 Jun 2018

Mk50312

====Pinout==== {{:electronic:datasheet:mostek:mk50312.png?400 }} 8-digit calculator, 9 function (+, -, x, /, %, $, SQRT, X^2, 1/X), seven memory functions Keyboard Matrix: KN KO KS Note: KS = KN && KO D0 CM D1 1 % D2 2 sum = D3 3 M-= M- D4 4 SQRT X^2 D5 5 1/X . D6 6 $ / D7 7 M+= M+ D8 8 XM x D9 9 MS - D10 0 MR + D11 C/CE Note: D0, D10, D11 are for keyboard matrix only
Taken from data for MK50311 chip which has the same pinout, I have assumed same functions, might be wrong ... The TRQ F-85 calculator, that uses this chip, has a switch with two positions 'N' and '∑', I'm not sure how this is connected. I think it may switch a line between the 'KS' column and the 'KO' column, so if that line is connected to the "=" key it would switch its function from "=" to "sum" going by the table above. (The wiring of the TRQ F-85 board confirms the keyboard digit->row associations) ((http://www.calcuseum.com/SCRAPBOOK/BONUS/09734/1.htm)) ====Calculators that used MK50312=== * [[http://www.datamath.org/Related/Corvus/Corvus_615.htm|Corvus 615]] * [[https://www.subito.it/informatica/calcolatrice-dumont-corvus-615-anni-70-salerno-240894912.htm|Corvus 615]] * [[:electronic:calculator:corvus804|Corvus 804]] * [[http://www.calcuseum.com/SCRAPBOOK/BONUS/48657/1.htm|F-84]], Electrónica Querol (TRQ) F84. ((Spain)) * [[http://www.calcuseum.com/SCRAPBOOK/BONUS/09734/1.htm|F-85]], Electrónica Querol (TRQ) F85. ((Spain))