PropBasic: SEROUT byte array (sanity check)

VonSzarvas · 2010-09-20 07:16

To output a set of byte codes with serout, should this work ?

CONFIGLCD     DATA    $F0,$F0,$07,$00,$08,$00,$A6,CR,LF

SEROUT TXPIN, BAUD, CONFIGLCD

Thank you.

VonSzarvas · 2010-09-20 07:42

... ah, it seems the 4th byte ($00) acts as a termination, so the rest of the bytes are not transmitted...

So I suspect my question should be, how to actually SEROUT a DATA label containing $00 ?

VonSzarvas · 2010-09-20 08:41

I solved it by adding a routine to JonnyMac's serial lib like this:

TX_DATA       SUB     1
TERMINATOR    CON     $FF

CONFIGLCD     DATA    $F0,$F0,$07,$00,$08,$00,$A6,CR,LF,TERMINATOR

And to transmit the data label:

TX_DATA CONFIGLCD

Here is the new sub I added to the serial lib:

'{$IFUSED TX_DATA}
SUB TX_DATA

   __param3 = __param1 ' Save param as __param1 overwritten by TX_BYTE

   DO
        RDBYTE __param3, __param2 ' Read byte from hub
        IF __param2 = TERMINATOR THEN EXIT
        TX_BYTE __param2
        INC __param3 ' Move to next byte in hub
   LOOP

ENDSUB
'{$ENDIF}

In the DATA definition, the last byte is the termination byte and not transmitted. This could be whatever you like- just change the CONstant definition.

I hoped to use -1 as the termination byte but it fails (I guess obviously as we are talking bytes). Maybe Bean could suggest a smarter way, but for now this does the job !

PropBasic: SEROUT byte array (sanity check)

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