Just a thought, you could go old skool . . .

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TXA (analog to serial) symbol

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String parameter = \x08\x22\x01\x00\x00? (do not use quotes)

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Volume level is connected to analog input

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Use AOS to generate a pulse on change of volume level, connect to trigger input

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Set format parameter to 258.

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No s+, no PITA, might be too simpl …………..

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Given Jonathons python script, you could use the following to always out the correct string when inputting a volume of 0 - 100:

CHANGE VOLUME
{
?? ?INTEGER i;
?? ?INTEGER SumOfBytes;
?? ?INTEGER Checksum;
?? ?STRING Command$[6];
?? ?
?? ?MAKESTRING(Command$, "\x08\x22\x01\x00\x00%s", CHR(VOLUME));
?? ?SumOfBytes = 0;
?? ?
?? ?FOR(i = 1 TO 6)
?? ?{
?? ???? SumOfBytes = SumOfBytes + BYTE(Command$, i);
?? ?}
?? ?
??? Checksum = (0xFF - SumOfBytes + 1) % 0xFF;
?? ?
??? STRING_OUT$ = Command$ + CHR(Checksum);
}

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