THOMSON VK231PS, Technical Manual

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43
FUNCTION DATA
KEYBOARD
The KEYBOARD FUNCTION keys are located between the sweep outputs of IK01 (Pins 71/72
or 18/19) and the function inputs of IK01 (Pins 67 through 70 or 9 through 12).
The keyboard function data are sent to servo control microcontroller IT001 via Output 21 or 25
of IK01. The serial transfer clock is present at 19 or 26 of IK01. This clock consists of 8-bit
bursts. The clock period is 16 µs.
REMOTE CONTROL
The remote control function code is a 12-bit serial word. It arrives at 48 of IT001.
It has the following composition:
A3 through A0 = 4 address bits
A3 A2 A1 A0
0 0 0 0
T0 = 1 bit. This bit changes state each time a key is pressed.
It makes it possible to distinguish between a continuous command and a
new command.
D6 through D0 = 7 function bits
READING FUNCTION CODE
5ms
2,5ms
640
µ
s
A3
A2 A1 A0 T0 D6
D5 D4 D3
D2 D1 D0