Parallel port -7, 8 parallel port – Acrosser AR-B1320 User Manual
Page 15
A
A
R
R
-
-
B
B
1
1
3
3
2
2
0
0
U
U
s
s
e
e
r
r
’
’
s
s
G
G
u
u
i
i
d
d
e
e
2-7
(9)
Divisor Latch (LS, MS)
Byte Data
LS
MS
Bit 0:
Bit 0
Bit 8
Bit 1:
Bit 1
Bit 9
Bit 2:
Bit 2
Bit 10
Bit 3:
Bit 3
Bit 11
Bit 4:
Bit 4
Bit 12
Bit 5:
Bit 5
Bit 13
Bit 6:
Bit 6
Bit 14
Bit 7:
Bit 7
Bit 15
Desired
Baud Rate
Divisor Used to
Generate 16x Clock
Present Error Difference
Between Desired and Actual
50 2304
---
75 1536
---
110 1047
0.026
134.5 857
0.058
150 768
---
300 384
---
600 192
---
1200 96
---
1800 64
---
2000 58
0.69
2400 48
---
3600 32
---
4800 24
---
7200 16
---
9600 12
---
14400 8
---
19200 6
---
28800 4
---
38400 3
---
57600 2
---
115200 1
---
Table 2-4 Serial Port Divisor Latch
2.8 PARALLEL
PORT
(1) Register Address
Port Address
Read/Write
Register
base+0 Write
Output
data
base+0 Read
Input
data
base+1
Read
Printer status buffer
base+2
Write
Printer control latch
(2) Printer Interface Logic
The parallel portion of the SMC37C669 makes the attachment of various devices that accept
eight bits of parallel data at standard TTL level.