309-509 Datasheet (RS Components)

309-509, Keyboard encoder

data lssuedNovember1984 4080 Keyboardencoder i.c.309-509 T|e RS2376 Keyboard Encoder l.C.

is a fully integrated P-MOS keyswitch encoding circuit, suitable for encoding a keyboard with up to 88 switches, plus shift and control, into a useable9 bit data code, i.e.the standard8 bit ASC ll datacode + one parity bit.

The RS2376offers the facilities of two key roll-over operation with N-key lockout and has userselectableodd or even parity and output polarity.A self contained oscillator and debouncec

309-509 Features

* oOne integrated circuit required for complete keyboard assembly. o Outputs directlycompatiblewith TTLor MOSlogic arrays. o External control provided for output polarity selection. . External control provided for selectionof odd or even parity. oTwo key roll-overoperation. o N-keylockout. o Self-cont