Digital I/O Control: Base+11 (Read/Write)
Bit:
7
6
5
4
3
2
1
0
Name:
DIOCTR
-
-
DIRA
DIRCH
-
DIRB
DIRCL
DIOCTR
Selects counter I/O signals or digital I/O lines C4-C7, on pins 21-24 of J14. If DIOCTR = 0, the pin
direction is as shown in the following table. If DIOCTR = 1, the pin direction is controlled by the
DIRCH bit.
Pin No. DIOCTR = 1 DIOCTR = 0
Pin direction, for
DIOCTR = 0
21
C4
Gate0
Input
22
C5
Gate1
Input
23
C6
Clk1
Input
24
C7
Out0
Output
This bit resets to 1.
DIRA
Port A direction.
0 = output
1 = input
DIRCH
Port C, bits 7-4, direction.
0 = output
1 = input
DIRB
Port B direction.
0 = output
1 = input
DIRCL
Port C, bits 0-3, direction.
0 = output
1 = input
Counter/Timer Bits 0-7: Base+12 (Read/Write)
Bit:
7
6
5
4
3
2
1
0
Name:
D7
D6
D5
D4
D3
D2
D1
D0
D0-D7
LSB for counter 0 and counter 1.
When writing to this register, an internal load register is loaded. Upon issuing a Load command, using
Base+15, the selected counter’s LSB register is loaded with this value.
When reading from this register, the LSB value of the most recent Latch command is returned.
Note: The value returned is NOT the value written to this register.
Diamond Systems Corporation
Athena II User Manual
Page 63
