IBM 1725 SLS Manual Do Utilizador

Cable Pinouts

B-9

Technical Specifications

Notes to the Table

Direction refers to the direction of signal flow as viewed from the 
printer.

Return denotes “twisted-pair return” and is to be connected at 
signal-ground level. When wiring the interface, be sure to use a 
twisted-pair cable for each signal and never fail to complete con-
nection on the return side. To prevent noise effectively, these 
cables should be shielded and connected to the chassis of the 
system unit and printer, respectively.

All interface conditions are based on Transistor-Transistor Logic 
(TTL) level. Both the rise and fall times of each signal must be 
less than 0.2 microseconds.

Data transfer must be carried out by recognizing the ACKNLG or 
BUSY signal.

The cable must have an overall braided shield, Belden 8345 or 
equivalent.

»

Note:

Connectors must have shielded housings. The overall shield must

be bonded to the shielded housings at both ends of the cable.

Serial

This table gives the pinouts for the printer end of the 25-pin RS-232 
cable.

1

Not Used

2

Transmit Data (TXD)

3

Receive Data (RXD)

4

Request to Send

5

Clear to Send(GND)

6

Data Set Ready (DSR)

7

Signal Ground

20

Data Terminal Ready