Sony AR-B1570 manual Parallel Port, Register Address, Printer Interface Logic, Data Swapper

	AR-B1570 User’s Guide
Desired Baud Rate	Divisor Used to Generate 16x Clock
300	384
600	192
1200	96
1800	64
2400	48
3600	32
4800	24
9600	12
14400	8
19200	6
28800	4
38400	3
57600	2
115200	1

Serial Port Divisor Latch

2.6 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

Registers’ Address

(2) Printer Interface Logic

The parallel port of the W83977F-A is for attaching 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.

(4) Printer Status Buffer

The system microprocessor can read the printer status by reading the address of the Printer Status Buffer. The bit definitions are described as follows:

7	6	5	4	3	2		1	0
						X	X	X

-ERROR SLCT PE -ACK -BUSY

Printer Status Buffer

NOTE: X presents not used.

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