View Full Version : Two Props One Serial Link

12-23-2009, 07:48 AM
·Hi Guys,
Im building up a board with two props and I wanted to talk to both of them through a pc and hoped to do this with only one FDTI chip.· Is that reasonable?· Any ideals on how to do this?
Thanks Greg

12-23-2009, 08:06 AM
You could have a master-slave config between the two Props ( only have the pc connected to one Prop) and use one of the cogs on the master to handle both the communication between the Props and between the master and the pc.
Would be pretty simple with FullDuplexSerial.

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Mike Green
12-23-2009, 08:28 AM
The receive line from the FTDI chip could be connected to both Prop chips. You'd have to have a jumper to select which Propeller chip would transmit to the FTDI chip. On the receive end, you'd need 2.2K resistors in series with each Prop input just to play it safe if one of them were to accidentally be programmed as an output.

12-23-2009, 04:47 PM
Thanks for that.· I thought about tying the receive and transmitt to both, but the problem was collision with the transmit.· Actually, I probably could solve that in the code.· I.E. talking only when spoken too.