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Last update: 13 September 2005

IC function:KEA (Keyboard Encoder Array)

Component documentation
IC numberManufacturerDocumentation
MCS1007MOS TechnologyPreliminary Datasheet March, 1973

Component versions
IC numberPackage
MCS100740-pin Ceramic DIP

Programmed components
IC numberChip descriptionChecksum
MCS1007-019

Pinout
PinTypeNameDescription
1PowerVGG-12V Power Supply
2..3InputØ2..Ø1Clock Input
4..12InputY1..Y9Row Signal inputs from Keyboard Matrix.
13..20OutputX1..X8Column Interrogate pulses supplied by KEA to Keyboard Matrix.
21..23
24InputRepeat OscillatorA low frequency square wave input to define the repeat frequency of the Strobe signal when in Repeat mode.
25InputData AcknowledgeA input level or pulse which cause immediate reset of Strobe and Error signals.
26InputBuffer ResetAn input level or pulse causing immediate reset of all data Bits (D1 to D8) and the Parity Bit.
27OutputKey IdleAn output signal indicating (when true) that no key is depressed on the Keyboard Matrix.
28OutputStrobeAn output signal which becomes true at the beginning of the second scan following a scan in which a new key depression has been detected. The signal remains true until a new key is depressed, or the Data Acknowledge signal is received. The Strobe signal will alternate in synchronism with the Repeat Oscillator signal when operating in the repeat mode.
29OutputErrorAn output signal which becomes true at the beginning of the scan following a scan in which an error condition occurred. Error conditions include:
1. Two new key signals in one scan.
2. New key signals in two successive scans.
The error signal, once set, remains true until: a new key is depressed; all keys are released; or the Data Acknowledge signal is received.
30OutputParityAn odd parity bit generated from the ROM data bits.
31
32..38OutputData Bit 7..Data Bit 1Encoded data word output. All bits change to correct level simultaneously one clock period prior to generation of the Strobe signal. Data bit remain valid only for the duration of the Strobe signal (unless reset by activation of Buffer Reset signal).
39OutputData Bit 8
40PowerVSS+5V Power Supply

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