Printing from the Atom

discussion of games, software, hardware & emulators relating to the Acorn Atom
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John Ferguson
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Printing from the Atom

Post by John Ferguson » Thu Apr 26, 2018 11:36 am

I am thinking of printing from the Atom.

I have yet to acquire a printer.

When I press control B to set the printer output the Atom locks up.

Could someone help me by saying whether this is normal while a printer is not connected, and if not, where I should look to overcome the problem?

John

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hoglet
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Re: Printing from the Atom

Post by hoglet » Thu Apr 26, 2018 12:05 pm

It's normal. It will be looping in this piece of the MOS waiting for the printer to be not busy:

Code: Select all

                                WAIT FOR PRINTER NOT BUSY

FF10  2C 01 B8  BIT #B801       Busy ?
FF13  30 FB     BMI #FF10       ..yes, wait for printer to be not busy
If you really want to verify this, try pulling Port A bit 7 to ground with a 470R (or there abouts) resistor. There is a 4K7 pullup on this signal, so the default value is BUSY is asserted (high).

Dave

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oss003
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Re: Printing from the Atom

Post by oss003 » Thu Apr 26, 2018 2:07 pm

Or remove the printercheck by typing !#208=!#208+3.

Atom Theory and Practice:
printer.png
Greetings
Kees

John Ferguson
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Joined: Sat Oct 07, 2017 11:35 am
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Re: Printing from the Atom

Post by John Ferguson » Thu Apr 26, 2018 3:21 pm

Thank you Dave and Kees.

I feel re-assured that nothing is wrong.

John

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