What is the pin-out for the TTL Serial Port pins?
**The TTL Serial Port is the USART2 module of the User processor and it is defined in the Robot Controller Reference Guide. Here it is again:
The left-most pin (labeled with a plus sign) is 5V.
The next pin is the transmit signal, TX2.
The third pin is the receive signal, RX2.
The right-most pin (labeled with a B) is ground.**
First, does PIC18F8520 contain an I2C bus? If yes, is the TTL port on FRC connected to the I2C bus? In MAP 18 C, are those I2C functions (OpenI2C(), StartI2C(), etc.) the functions to communicate with devices on the I2C bus? Will any of those functions block the program if the device does not exist?
Yes, the PIC18F8520 does contain an I2C bus. The TTL port on the FRC is not connected to the I2C bus. The TTL port is a separate port on the uP. The RC can NOT control I2C devices. The I2C bus is not available on external pins and no other devices can connect to the I2C bus. The I2C bus is used to communicate between the Master and User processors. The I2C bus is reserved. DO NOT use any I2C functions or you will cause errors.