HP82143A printing - two views of the same medal

[ThomasF]

(07-17-2024 02:10 AM)Christoph Giesselink Wrote:  I attached the actual output of v1.17, the output of v1.18beta2 and the send byte sequence (svn.bin) received by the printer simulation.

Hi Christoph,

One thing I noticed is that the 'staircase' is printed by accumulating 45 bytes in total (3*15 columns).
The two 'barcode' lines are composed of exactly 44 columns, with the sequence [00,ab,bd,00] after the first and [e0] after the second. In both cases this results in a linefeed following the 'barcode'.

So, if the buffer is full (after 44 bytes), there is as you mentioned still the three bytes [00,00,d0] left to handle.

My question is who generates the linefeed after the staircase?

Both 'barcodes' are followed by a linefeed (but the columns are right justified), but the staircase is left justified and it looks like the two extra bytes [00,00] are added as empty columns just before the first "TRY .." in your output, and the [d0] byte is treated as "abort graphics mode" (so text can follow).

The first [00] bytes after the first 'barcode' is probably printed on the line following the 'barcode', but is not visible on the paper, as I assume the [ab,bd] are treated as control characters.

Just my 2 cents ...

Cheers,
Thomas