Printers

At least two printer types are supported: Serial Impact Printer with IO addresses 5, 6, 7 and Dot Matrix Printer with IO address 8.

Printer status

For the printer to be used by the ROS, it apparently has to be ‘selected’. I am not sure how it is selected practially, but the status of a selected printer is bit 0. The ‘Q1 ASM IO address’ manual only states this explicitly for the Dot Matrix Printer but it seems to be valid for the Serial Impact Printer too.

I originally thought that status 0x00 meant printer is ready, no errors. So the emulator returned this value for both printers.

But running the program FMOMS I got the following error message:

../_images/noprinter.png

Output from FMOMS program

which lead me to further progress on the printer interface.

Printer status

Bit

Serial Impact Printer (0x5)

Dot Matrix Printer (0x8)

7

busy

busy

6

error

fault

5

out of ribbon

paper out

4

0

3

0

2

0

1

0

0

Printer Selected (inferred)

Printer Selected