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KEYPAD PORT SECTION 9
Page 9-2 RPC-320
The second example uses ON KEYPAD to generate an
interrupt every time a key is pressed.
10 ON KEYPAD1000
.
.
.
500 GOTO 500
1000 PRINT KEYPAD(0)
1100 RETURN
Line 10 sets up the tasker for keypad interrupts to start at
line 1000. Line 500 loops on itself for demonstration
purposes.
Line 1000 prints out the key pad position pressed.
Elements of the previous program can be com bined with
this one to produce keypad strings.
KEYPAD PORT PIN OUT - J5
The keypad port uses ports B and C from an 82C55.
Lower port C is configured as an input. Upper port C
and port B bits 0 and 1 are outputs.
The table below lists J5' s pin out, 82C55 port and bit,
and its intended function.
Pin 82C55 Function
Port/ bit
1 C/0 Row 1
2 C/6 Column 3
3 C/5 Column 2
4 C/1 Row 2
5 C/2 Row 3
6 C/4 Column 1
7 C/7 Column 4
8 C/3 Row 4
9 B/0 Column 5
10 B/1 Column 6