1. It depends on how far apart they are and how fast you need to transfer data. Over short distances (<10cm) a parallel bus is fastest because it can transfer a whole byte at a time. Over longer distances it is more practical to use a serial system which transfers on ebit at a time so is slower but uses less wiring.
2. Yes, but if you want to send say 32 bits to an 8-bit device you have to split it into four 8-bit sections and send them individually. You can only transfer as much in one step as the smaller processor can manage.
3. USB requires a host system. If one is a host (I do not have the data sheets here to check) yes you can do it. You cannot connect two USB slave (client) devices directly together.
there are some protocols like I2C,SPI etc. try to use that to communicate if the distance is less. if its larger distances then its better to use modbus protocol through rs485
there are number of alternatives
1. UART to UART is probably the simplest and you can use hardware flow control if required
2. I2C or SPI if the devices are close to each other
3. USB - make one PIC32 USB host and the second USB device
4. wired Ethernet or wireless for distances over 10 metres
**broken link removed**
i think UART communication will be best if these are the free for that.Bcoz no need to consider master and slave.If they are engaged then u have to go for I2C, SPI or parellel port communiaction.
i think UART communication will be best if these are the free for that.Bcoz no need to consider master and slave.If they are engaged then u have to go for I2C, SPI or parellel port communiaction.