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Transmission from two PICs to one PIC with 2 USART

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Sep 16, 2009
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Hello friends... I am trying to establish 2 independent serial transmission links using 2 separate PICs and receive those two transmitted bytes by a single PIC having 2 USART. I am using an interrupt based approach, so when a byte is received, it handles the received byte and display it. Is there a better idea or experience dealing with 2 USART?

Also, I wish to transmit these two received bytes on the PIC to the PC. Can I transmit 2 parallel lines to the PC or I have to use only one transmission line and send the data one bye one in loop?

Everything is just one way transmission. Simply, receive 2 different data, display it, and then transmit the same data to the PC.

Thank you for your support

so long as your PIC has sufficent USARTs it can communicate with two other PICs and a PC otherwise if you only have two USARTs
1. but have peripheral pin select you can switch the USARTs between pins.
2. if you only wish to transmit to the PC you can use the Rx of a USART to receive data from a PIC and the Tx to transmit data to the PC (assuming same baudrate).

Another possible option:

If your choice of PICs support it you could also implement an I2C bus, designate one PIC as a master and all other PICs as slaves sharing the same I2C bus for communication among the PICs. Then use an USART on the master to establish a RS-232 with the PC.

I've used this method several times in the past. It is particularly useful if you have other I2C devices in the chain.

I2C communication between PICs

**broken link removed**

if the PICs have Canbus another option is to make a small canbus network to interconnect the PICs

Good point Horace1, that idea crossed my mind as well.

The drawback is the coding for CANbus is a little more involved.

The other option is SPI. However, I see no real advantage of it or I2C.
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I don't want to use SPI, CAN, I2C, but only USART.

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