iSys V8.5e Thermal Printer User Manual

Page 59

C. APPENDIX

CENTRONICS INTERFACE BOARD

The new Centronics adapter (rev1-2) implements some improvements over the previous (rev1-1) adapter card.

These include:

a. Rev 1-2 cards will accept either of the two data transfer methods described below automatically; no

switches or jumpers required.

b. Reliable data transfers using up to 40 ft length of shielded cable.

c. Rev 1-1 adapter cards exhibit inconsistent data transfer with newer generation PC.’s equipped with high

speed integrated Centronics parallel ports.

The following are two transfer formats that can be used with the optional V8.5E Centronics parallel adapter:

Standard transfer format

To place the V8.5E Centronics adapter in raster mode, the following 3 bytes (hex) must be sent to the

Centronics adapter card:

1B, 2A, 00

Once these 3 bytes are sent, rastered plot data can be sent to the plotter as follows:

V8.5E bytes/scan menu setting

bytes/scan raster data

216

264

g1-g4

1728

Once the V8.5E Centronics adapter is set to raster mode it will remain in raster mode until the init line of the

host Centronics port is pulsed or the plotter power is cycled. This will return the adapter to print mode.

Enhanced transfer format

For more flexibility, a 6 byte header can be sent before each scan of rastered data. This header allows

variable bytes/scan plotting. The Centronics adapter also returns to print mode at the end of every scan

using this transfer method. This allows the five 1B, 4X commands or the standard ASCII control codes listed

below in section 3 to be used during plotting. The format of the 6 byte header is:

1B 2A 72 XX YY 01 where

XX = high byte of the

number of bytes/scan

YY = low byte of the

number of bytes/scan