Gandalf_Sr
Member level 1
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I want to have 2 PICs communicating with each other over a DC power line that's running at 12V and maybe carrying 10A. It will be driving motors so there will me some noise. Max distance is probably around 50m. The attachment shows the basic approach but I'm not sure how best to approach putting the data onto the power line.
What I've read so far suggests that a frequency of 1 MHz is fairly easy to filter on/off the power line but the data rate of I2C, SPI isn't that high, it would vary, and I can't just push serial data onto the power line, or can I?
If I need some sort of modulation, how about PSK or something?
Anybody like to chip in with suggestions?
Other Info
The data will have to be bi-directional, there will only ever be 1 master and 1 slave - one on each end, there will only be 1 signal wire - I'm thinking of sending the data and power over coax with the +ve and signal on the inner conductor.
Amount of data is fairly low so I am prepared to add a lot of parity, multiple transmission and acknowledgment etc. to get reliable comms.
What I've read so far suggests that a frequency of 1 MHz is fairly easy to filter on/off the power line but the data rate of I2C, SPI isn't that high, it would vary, and I can't just push serial data onto the power line, or can I?
If I need some sort of modulation, how about PSK or something?
Anybody like to chip in with suggestions?
Other Info
The data will have to be bi-directional, there will only ever be 1 master and 1 slave - one on each end, there will only be 1 signal wire - I'm thinking of sending the data and power over coax with the +ve and signal on the inner conductor.
Amount of data is fairly low so I am prepared to add a lot of parity, multiple transmission and acknowledgment etc. to get reliable comms.