Hi folks

all excited yesterday finally after much time and lots of listening to the
LIST got my 16F84 @ 4MHz to record a Sony IR command and successfully
retransmit.

TMR0 is used to generate periodic (26us) increments of the contents of a
memory location.  Then interrupt on change RBIF is used to point to the next
memory location.

The result is a string of bytes containing the duration in multiples of 26us
of each mark and space of the IR code.  This works fine for the Sony as it
uses 13 bits therefore I use 26 bytes to record the pattern.  (I later plan
to store this in external EEPROM)

I have discovered other remotes (see
www.users.bigpond.com/jkrichards/Pic/PicPage.htm click on trace.bmp) use up
to 34 bits therefore I need 68 bytes, this is all of the 16F84 data memory.

I have tried to think of ways to compress the data but it needs to be
captured before it can be processed.

Another idea I entertained was to generate the periodic interrupt and test
for highs and lows and record this as a big long string of bits.  But this
would use about 3000 bits or 375 bytes for a code 60ms in duration..

Also for it to be truly universal I cant make any assumptions about
bit/pulse width.  It should be able to faithfully record any brand.

Any thoughts on a better process that does not use so much valuable data
space will be most welcome.

I am more than happy to elaborate on the existing design if anyone is
interested in doing similar things.

Justin

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