I'm suspecting this isn't a Perl/XS problem, but I'm head scratching. After adding some print statements in core locations in the C code just prior to the data being sent to the LCD, I get the exact same output between the C example and the Perl example, which leads me to believe the way I'm sending data in through Perl/XS is fine:

# C

sndcmd: 40
sndcmd: 12
sndcmd: 12
sndcmd: 12
sndcmd: 1
sndcmd: 2
sndcmd: 6
sndcmd: 20
sndcmd: 1
sndcmd: 2
sndcmd: 128
sndcmd: 80
sndcmd: 31
sndcmd: 17
sndcmd: 17
sndcmd: 21
sndcmd: 31
sndcmd: 17
sndcmd: 17
sndcmd: 31
put: 2
sndcmd: 2

# Perl

sndcmd: 40
sndcmd: 12
sndcmd: 12
sndcmd: 12
sndcmd: 1
sndcmd: 2
sndcmd: 6
sndcmd: 20
sndcmd: 1
sndcmd: 2
sndcmd: 128
sndcmd: 80
sndcmd: 31
sndcmd: 17
sndcmd: 17
sndcmd: 21
sndcmd: 31
sndcmd: 17
sndcmd: 17
sndcmd: 31
put: 2
sndcmd: 2

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In reply to Re: External C function called through XS not Doing The Right Thing by stevieb
in thread [SOLVED (workaround)]: External C function called through XS not Doing The Right Thing by stevieb

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