![](/images/new-backgrounds/1188150/188150387x1.webp)
[ 3 ] Interface Specifications
131
|
|
| 25 | 14 |
|
|
|
|
|
| |||
|
|
|
|
|
| |
Pin No. | Signal | Functions |
| Signal Input/Output | ||
| External | |||||
|
|
|
|
| device | |
|
|
|
|
|
| |
1 | FG | Frame ground |
|
| Ñ | |
2 | SD | Send data |
|
| → | |
3 | RD | Receive data |
|
| ← | |
4 | RS | Request to send |
|
| Ñ | |
5 | CS | Ready to send |
|
| Ñ | |
6 | DR | Data set ready |
|
| Ñ | |
7 | SG | Signal ground |
|
| Ñ | |
8 | CD | Carrier detect |
|
| Ñ | |
20 | ER | Data terminal equipment ready |
| Ñ | ||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Shown below is a diagram of the internal connection in the
Host computer, |
|
|
|
| ||
modem, or |
|
|
|
|
|
|
other devices |
|
|
|
|
|
|
Signal |
|
|
|
|
|
|
Pi | n | No. |
| |||
Name |
| |||||
|
|
|
|
|
| |
|
|
|
|
|
| |
FG | 1 |
|
| Not used. | ||
| ||||||
SD | 2 |
|
|
| ||
|
|
| ||||
|
| |||||
RD | 3 |
|
|
| ||
|
|
Interface
Circuitry
Optical Interface |
| |
Optical |
| |
Communications | BHT | |
Interface | ||
| ||
Circuitry |
|
RS | 4 |
CS | 5 |
DR | 6 |
ER | 20 |
CD | 8 |
SG | 7 |
174