RS 224-9847 Instruction Leaflet

10550
Issued November 1996
Thermal Printer Interface
Board
Instruction Leaflet
RS stock no. 224-9847
1. Introduction
These notes describe connection procedures to be adopted for the RS Thermal Printer
Interface. Please read carefully before making any connection.
The interface board is recommended for use with RS printer mechanisms; 224-9831 and
224-9881.
2. Power supplies and EMC
2.1 Power supply requirements
The interface board requires an external power supply of +5Vdc. The current drawn will
depend on the printing density, but will typically be between 1A and 3A: refer to section
6.1 for full specification.
2.2 Power supply warning
Momentary interruptions to, or reductions in the voltage of the power supply can result
in a fault condition from which the printer cannot recover until power is completely
removed and correctly restored. The user must ensure that the supply will not be teased
in this way. The power supply must not be taken above 6.0V, or reversed, even under
transient conditions. Particular attention should be paid to the power arrangements in
vehicle or battery-operated applications, where load dump transients or reversal of
replaceable batteries might occur. Refer to section 6.1 for more power connections.
2.3 EMC Advice
Please note that the interface board to which this application data refers is considered to
be a component and is not certified for Electro-Magnetic Compatibility (EMC). The
system integrator using this item must assume responsibility for EMC between the
interface and its environment, both for emissions and susceptibility.
3. Paper feeding, loading and demonstration mode
On power-up, the printer motor will run for a few seconds, while the controller identifies
the mechanism fitted and carries out internal calibration. It will feed out approximately
four lines of paper, in accordance with the manufacturers recommendation.
Pressing the paper feed button advances paper up to 4 lines per second. If the paper
feed button is pressed during power-up, a message including the firmwave version
number and some encoded calibration data, and the full character set will be printed,
this can be repeated by pressing the feed button again. Powering the interface board off
and on will revert to normal operation. The demonstration feature can be suppressed
under software control.