Technical information

2.3.6 DFA01 Asynchronous Controller with Integral Modem
The DFA01 is an asynchronous serial controller that emulates the DZQ11.
It has two lines, each with a DF224-compatible integral modem.
Functional Information
Supported modulation protocols Bell 103J
Bell 212A
CCITT V.22
CCITT V.22–BIS
Split-speed operation Both lines
Flow control (XON/XOFF) No
Supported data formats 8 programmable formats (each with 1 start bit)
• 5, 6, 7, or 8 data bits, 0 or 1 parity bit, and 1
stop bit
• 5, 6, 7, or 8 data bits, 0 or 1 parity bit, and 2
stop bits
Modem control Full
Ordering Information
DFA01–AF Field-installed kit
Performance
Transmit data transfers Single-character programmed transfers
Receive data transfers Single-character programmed transfers
Transmit buffer size One character for programmed transfers
Receive buffer size 64-character FIFO
Supported baud rates 8 programmable baud rates: 50, 75, 110, 134.5,
150, 300, 1200, 2400
1
Throughput at maximum baud rate 1200 bytes/second
1
The serial line is capable of baud rates up to 9600 baud. However, because the modem is
restricted to speeds of 0–300, 1200, and 2400 baud, all other baud rates are considered illegal
and pass meaningless data.
2–50 VAX 4000 Model 200 Technical Information