In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Zoot wrote:

Some of what you describe sounds like it might be noise on the lines. But looking at the flow of your main program, there is nothing to prevent a dimmer level value of 126 to mistaken for a new sync byte:

[code]
IF working_byte = 126 THEN
byte_count = 1
\mov tx_high,working_byte
\clrb tx_low.7 		' set start bit
\mov tx_count,#10 	'1 start + 8 data + 1 stop bit
ELSE
INC byte_count
ENDIF
[/code]

I would either capture all relevant bytes to a buffer, then parse the relevant bytes once I have them all, or use a simple state machine. You could use the status of byte_count, a la:

[code]
IF byte_count = 0 THEN    ' only check once for a packet
  IF working_byte = 126 THEN
  byte_count = 1
  \mov tx_high,working_byte
  \clrb tx_low.7 		' set start bit
  \mov tx_count,#10 	'1 start + 8 data + 1 stop bit
  ENDIF
ELSE
  INC byte_count
ENDIF

IF byte_count = 2 THEN
  \mov tx_high,working_byte
  \clrb tx_low.7 		' set start bit
  \mov tx_count,#10 	'1 start + 8 data + 1 stop bit
ENDIF

IF byte_count = 3 THEN ' as before
'...
ENDIF

' now this part I don't get -- how would byte_count ever be larger than 19 unless it's a new packet? 
' seems like the tx'ed byte should be sent on byte_count = 19 (the last byte of the packet)

IF byte_count = 19 THEN
  READ Scurve+working_byte, Level17
ENDIF

IF byte_count >= 19 THEN
\mov tx_high,working_byte
\clrb tx_low.7 		' set start bit
\mov tx_count,#10 	'1 start + 8 data + 1 stop bit
ENDIF

[/code]





[/code]

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