Pinstamp

TASK:

Do more with less.

Write PLC code for an ancient Telesis pinstamp printer

from the early 1990's, replacing a flaky ink jet printer

that never worked properly

Existing control system is an AB SLC500 PLC controlling

a sixteen station assembly line.

An AB basic module was used to communicate to the ink jet.

Our options were:

1) Modify basic module code to suit ancient pinstamp

2) Find another way of doing it since we were in a hurry

and didn't have enough experience with the AB system

to do it in time.

We opted to take an existing OMRON CQM1 PLC that we had

gathering dust in the corner, and write code for the pinstamp

Our part model and reject codes would be sent from the AB

discretely as binary inputs to the CQM1

Using the CQM1 RS-232 port, the Telesis functions strictly

as a printer with no confirmation signals sent back to the CQM1

Having installed a clock module in the CQM1 we were able to extract

the Julian day and year and print it along with the model # and

reject code .

Not exactly the finest example of modern technology, but it

works.

Who said that OMRON and AB can't get along!

P.S. - DM memory saved in project!