Little Board/P5x Technical Manual

Table 2– 22 lists the parallel port register bits.

Table 2– 22. Parallel Port Register Bits

Register

Bit

Signal Name

 

Active

J15

DB25F

or Function

In/Out

High/Low

Pin

Pin

 

 

 

 

 

 

 

DATA

0

PD 0

I/O

High

6

2

(378h)

1

PD 1

I/O

High

10

3

 

2

PD 2

I/O

High

14

4

 

3

PD 3

I/O

High

18

5

 

4

PD 4

I/O

High

22

6

 

5

PD 5

I/O

High

26

7

 

6

PD 6

I/O

High

30

8

 

7

PD 7

I/O

High

34

9

STATUS

0

TMOUT

In

---

---

---

(379h)

1

0

---

---

---

---

 

2

0

---

---

---

---

 

3

ERROR*

In

Low

8

15

 

4

SLCT

In

High

50

13

 

5

PE

In

High

46

12

 

6

ACK* (IRQ)

In

Low

38

10

 

7

BUSY

In

High

42

11

CONTROL

0

STB*

Out*

Low

2

1

(37Ah)

1

AUTOFD*

Out*

Low

4

14

 

2

INIT*

Out*

High

12

16

 

3

SELIN*

Out*

High

16

17

 

4

IRQE

---

High

---

---

 

5

PCD

---

High

---

---

 

6

1

---

---

---

---

 

7

1

---

---

---

---

* Can also be used as input (see text).

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Image 47
Ampro Corporation P5X manual DB25F