AR-B1375/AR-B1376 User s Guide
2-8
(9) Divisor Latch (LS, MS)
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 ---
Table 2-7 Serial Port Divisor Latch
(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
Table 2-8 Registers’ Address
(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.
(3) Data Swapper
The system microprocessor can read the contents of the printer’s Data Latch through the Data Swapper by reading
the Data Swapper address.