programming • Re: Sending Teletext over Serial

Code:

 DEFPROCVA(n$):LOCALq,r:q=OPENINn$:IFq=0 THEN VDM%=FALSEIF VDM% = FALSE ENDPROCJJ%=q:REPEATr=BGET#q:VDUr:IFr=13VDU10UNTILEOF#q:JJ%=0:CLOSE#q:PROCW:ENDPROC

Why so complicated? A teletext frame is simply a run of characters:
FOR A%=0 TO 959:VDU mem%?A%:NEXT A%

Any other way of displaying a teletext frame is simply a variation on that, eg: ttxt_display(). For instance, *TTXTYPE does the equivalent of:
DEFPROCttx_type(fn$):in%=OPENIN(fn$):IF in%=0:ENDPROC
n%=0:REPEAT:VDU BGET#in% OR &80:n%=n%+1:UNTIL n%>919 OR EOF#in%
CLOSE#in%:ENDPROC

When saving a teletext screen, the saver should ensure that all the contents are &20-&9F, which all the teletext editors I know do, and certainly the ABZ editor and tools do. Are you "breaking" the frame data up when sending it over a serial stream? Again, it's just a data block, all you need to do is something like FOR A%=0 TO size-1:PROCser_send(mem%?A%):NEXT A%.

Statistics: Posted by jgharston — Thu Feb 01, 2024 10:20 pm

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