Microchip Technology AC164145 User Manual

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Utility-band BPSK 6.0 kbps PLM PICtail™ Plus Daughter Board User’s Guide
DS75019A-page 28
© 2011 Microchip Technology Inc.
On reset, the receiver sends the application configuration summary over the UART. 
Then, every 5 seconds, it prints all packet statistics in a human-readable form. By 
increasing the debug level upon compilation, it is also possible to send detailed reports 
about each frame. This option is disabled by default. The detailed reports have the 
following format:
• −: Preamble character received
• _: Non-preamble character received out of frame
• <: Frame has started
• ?: Bad payload byte received
• #: The frame has reached the CRC fields
• !: Invalid CRC
• >: Frame has ended
• /: Frame was truncated
The UART configuration for this demonstration is:
• 115200 bps
• 8-N-1
• No flow control
3.2.5
Talk Demonstration
This demonstration implements character level communication.
1. Connect two serial port terminal emulators (such as HyperTerminal) to the 
RS-232 ports of a pair of Explorer 16 Development Boards.
2. Type your message in one of the terminal windows.
As soon as the Enter key is pressed (i.e., a CR character is sent), the message will be 
transmitted via the modem interface, preceded by an 8-byte synchronization preamble, 
and should be received by the second device and printed in the other terminal window. 
The message buffer size is 80 characters. If the CR character does not appear, the 
message will be transmitted after the 80th character has been received. Except for the 
CR character, no other characters have any special meaning and everything that 
appears at the serial port input, will eventually get transmitted via the modem output.
As there is a difference in transmitting speeds, the serial port being much faster than 
the modem interface, care must be taken not to overflow the input. When the modem 
is transmitting its current buffer, it silently ignores everything that it receives via the 
serial port. The UART configuration for this demonstration is:
• 19200 bps
• 8-N-1
• No flow control