Since it's likely that my incoming data will be 180 deg phase inverted,
I'm using a different scheme to transmit data.

I transmit 500 uSec of '+1' followed by 500uSec of '-1' for
a 1. I transmit 250uSec of '+1' followed by 250uSec of '-1' for
a 0.

Then I just send bits - I check some 380 uSec after seeing a positive
transition and if the pin is 1, it's a 1.

I transmit about 1K of data, which ends with a CRC. After recording the unit res
ets.

Sooo... my question is, anybody have any opinions on the advisability
of making some sort of sync pulse every 8 or 16 bits?

It's a 1 way channel, so I really
can't do a retransmit request, hence complex error detection is
irrelevant. If the CRC (16 bit) doesn't match, I flash an LED and
the user tries again.


--
Anniepoo
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