maemo.org - Talk - View Single Post - [] Jolla OtherHalf UART/232 Interface

	kimmoli	2014-01-22 , 20:51
	Posts: 562 \| Thanked: 2,744 times \| Joined on Dec 2013 @ Espoo, Finland	#16

Originally Posted by Zeta

Wouldn't the proper way to do this be that the chip is configured with the expected 1200 bauds and modulate it after (with an ne555 like or an I2C PWM expander if its period needs to be software controlled).

That is one possiblity... but i like to do things inside-out... (or atleast try)

Originally Posted by Zeta

something like "cat /dev/xxx" would allow to see directly the received value (and not a list of 0x0 or 0xF for each individual bit) ?

no intention to receive "remote control" data here, just transmit.
transmit can be done to work like echo "123" > mytransmitthingy with piece of software.

Originally Posted by Zeta

there may be problems with the start/stop bits with this proposal. Don't know if they are the same on IR than with say a RS232 line, so that the UART would understand them correctly ?

In sending bit '1' there is no problem with start/stop's, but when sending '0', the stop bit gives a pulse of half period of 38kHz every 10th period of that. Hopefully that is filtered out by the IR receiver.
One possibility is to stop transmitting at all when '0' but to get proper timing is pain.

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