Port status register, host, Register bit assignment – Digi NS9750 User Manual
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Register bit assignment
Port Status register, host
Address: 9040 0104
Register bit assignment
Bits
Access
Mnemonic
Reset
Description
D31:08
N/A
Reserved
N/A
N/A
D07:00
R
pd
N/A
Printer data pins
Allows the CPU to read the status of the 8-bit data bus
directly.
Table 399: pd — Printer Data Pins register
Bits
Access
Mnemonic
Reset
Description
D31:04
N/A
Reserved
N/A
N/A
D03
R
N_AUTOFD
N/A
Allows the CPU to read the status of the host control
pins directly.
The meaning of each bit varies, depending on whether
the mode is compatibility, nibble, byte, or ECP.
D02
R
N_INIT
N/A
D01
R
N_SLCTIN
N/A
D00
R
N_STROBE
N/A
Table 400: psr — Port Status register, host
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved
Reserved
N_
AUTOFD N_INIT
N_
SLCTIN
N_
STROBE