BBC *Status Command (and odd characters)

[RWAP]

When printing the output of the BBC's *STATUS command, the output on screen is:

Page24.jpg (147.18 KiB) Viewed 5607 times

However, when printed, the output is:

Retro-Printer Output.jpg (44.71 KiB) Viewed 5607 times

Now, we believe that this was correctly formatted on the Epson RX-80.

However, looking at the source, apart from the LF and CR codes, the only non-printable characters sent for the bottom half by the BBC are chr(131) - $83 and chr(135) - $87 - there are no tab characters or anything.

According to the ESC/P manual, these characters relate to :
chr(131) - no action
chr(135) - BEL

So, what is the BBC doing? The only reference I can find is that these are used by the BBC to control colours (in Teletext mode), although that is not visible on the scren shot.

Any ideas?

[RWAP]

Hmm - the *STATUS command appears to be from an add-on ROM, my guess is that a dot-matrix printer would have the same issue printing this output - more information is needed from the user!

[RWAP]

Thanks to the guys over on Stardot, we have at least managed to figure out a version of a ROM which provides a similar output.

https://stardot.org.uk/forums/viewtopic.php?f=2&t=16467

From that, it is clear that the control characters 131 and 135 are being used as colour controls - but the BBC prints a space where the control character would otherwise appear.

Presumably an ESC/P printer would therefore produce the same output as the Retro-Printer module - the ESC/P programming reference manual does not appear to indicate that a space is printed when these upper control codes are received.

I guess the question therefore is whether there would be any merit in a Teletext printer convertor (which would be in addition to the ESC/P and PCL convertors). It would be based on the explanation at http://central.kaserver5.org/Kasoft/Typ ... /Ch28.html