Interface Specifications
Parallel Interface
Data format: | ||||
Synchronization: |
|
|
|
|
STROBE pulse | ||||
Handshake timing: |
|
|
| |
BUSY and ACKNLG signals | ||||
Signal level: | TTL compatible | |||
Connector: | ||||
Pin assignments
Signal | Return |
|
|
|
|
|
|
|
|
|
Pin | Pin | Signal | Direction |
| Description | |||||
|
|
|
|
|
|
|
|
|
|
|
1 | 19 |
|
|
|
| IN |
|
| pulse to read data. | |
|
| STROBE |
|
|
| STROBE | ||||
|
|
|
|
|
|
|
|
|
|
|
2 | 20 |
|
| DATA 0 | IN | These signals represent | ||||
3 | 21 |
|
| DATA 1 | IN | information in bits 0 to 7 of | ||||
4 | 22 |
|
| DATA 2 | IN | parallel data respectively. | ||||
5 | 23 |
|
| DATA 3 | IN | Each signal is at HIGH level | ||||
6 | 24 |
|
| DATA 4 | IN | when data is logical 1 and | ||||
7 | 25 |
|
| DATA 5 | IN | LOW when it is logical 0. | ||||
8 | 26 |
|
| DATA 6 | IN |
|
|
| ||
9 | 27 |
|
| DATA 7 | IN |
|
|
| ||
|
|
|
|
|
|
|
|
|
|
|
10 | 28 |
|
| OUT |
| About a | ||||
| ACKNLG |
|
| |||||||
|
|
|
|
|
|
|
|
| indicates data has been | |
|
|
|
|
|
|
|
|
| received and the printer is | |
|
|
|
|
|
|
|
|
| ready to accept more data. | |
|
|
|
|
|
|
|
|
|
|
|
11 | 29 |
|
| BUSY | OUT |
| A HIGH signal indicates the | |||
|
|
|
|
|
|
|
|
| printer cannot receive data. | |
|
|
|
|
|
|
|
|
| The signal goes HIGH in the | |
|
|
|
|
|
|
|
|
| following cases: | |
|
|
|
|
|
|
|
|
| 1) During data entry | |
|
|
|
|
|
|
|
|
| (for each character) | |
|
|
|
|
|
|
|
|
| 2) During initialization | |
|
|
|
|
|
|
|
|
| 3) During self test, | |
|
|
|
|
|
|
|
|
| demonstration, and | |
|
|
|
|
|
|
|
|
| ||
|
|
|
|
|
|
|
|
| 4) During a | |
|
|
|
|
|
|
|
|
|
|
|
Technical Specifications |