UNIDENTIFIED
1200/300 BAUD MODEM
|
Modem Type |
Data (synchronous/asynchronous) |
|
Maximum Data Rate |
1200bps |
|
Data Bus |
8-bit ISA |
|
Data Modulation Protocol |
Bell 103 & 212A, ITU-T V.22 |
|
Error Correction/Compression |
Unidentified |

|
CONNECTIONS | |||
|
Purpose |
Location |
Purpose |
Location |
|
Line-in |
J1 |
Line-out |
J2 |
|
INTERRUPT SELECT - JP1 | ||||
|
í IRQ |
Jumper A |
Jumper B |
Jumper C |
Jumper D |
| » IRQ4 |
Open |
Open |
Closed |
Open |
|
í IRQ2 |
Closed |
Open |
Open |
Open |
|
í IRQ3 |
Open |
Closed |
Open |
Open |
|
í IRQ5 |
Open |
Open |
Open |
Closed |
|
ADDRESS SELECT | ||
|
í COM/Address |
SW1/1 |
SW1/2 |
| » COM1/3F8h |
Off |
Off |
|
í COM2/2F8h |
Off |
On |
|
í COM3/3E8h |
On |
Off |
|
í COM4/2E8h |
On |
On |
|
RECEIVED LINE SIGNAL DETECT BIT (RLSD) | |
|
í Setting |
SW1/3 |
| » RLSD bit reset/carrier detect status written to modem status register. |
Off |
|
í RLSD bit written to modem status register. |
On |
|
DATA TERMINAL READY (DTR) | |
|
í Setting |
SW1/4 |
| » DTR bit status written to the UART modem control register. |
Off |
|
í DTR bit is ignored. |
On |
|
PROTOCOL SELECT | |
|
Protocol |
SW1/5 |
| » Bell 103 & 212A enabled. |
Off |
|
í CCITT V.22 enabled. |
On |
|
MAKE/BREAK RATIO | |
|
í Setting |
SW1/6 |
| » 39/61 ratio (Bell standard). |
Off |
|
í 33/67 ratio (CCITT standard). |
On |