Little Board/P5x Technical Manual
2–29
Table 2– 22 lists the parallel p ort reg ister bits.
Table 2– 22. Parallel Port Register Bits
Register
Bit Signal Name
or Function
In/Out Ac tive
High/Low J15
Pin DB25F
Pin
DATA
(378h) 0
1
2
3
4
5
6
7
PD 0
PD 1
PD 2
PD 3
PD 4
PD 5
PD 6
PD 7
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
High
High
High
High
High
High
High
High
6
10
14
18
22
26
30
34
2
3
4
5
6
7
8
9
STATUS
(379h) 0
1
2
3
4
5
6
7
TMOUT
0
0
ERROR*
SLCT
PE
ACK* (IRQ)
BUSY
In
---
---
In
In
In
In
In
---
---
---
Low
High
High
Low
High
---
---
---
8
50
46
38
42
---
---
---
15
13
12
10
11
CONTROL
(37Ah) 0
1
2
3
4
5
6
7
STB*
AUTOFD*
INIT*
SELIN*
IRQE
PCD
1
1
Out*
Out*
Out*
Out*
---
---
---
---
Low
Low
High
High
High
High
---
---
2
4
12
16
---
---
---
---
1
14
16
17
---
---
---
---
* Can also be used as input (s ee text).