Chameleon-PIC Nurve Networks, Chameleon-PIC Datasheet - Page 143

• Manufacturer Part Number: Chameleon-PIC
• Description: MCU, MPU & DSP Development Tools PIC24 & PROPELLER DEV SYSTEM (SBC)
• Manufacturer: Nurve Networks

Specifications of Chameleon-PIC

• Processor To Be Evaluated: PIC24
• Data Bus Width: 16 bit
• Interface Type: USB, VGA, PS/2, I2C, ISP, SPI
• Operating Supply Voltage: 3.3 V, 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

_________________________________________________________________________________________________
Function Prototype:
Description:
Example(s):
SYS_ConfigureClock(MAX_FCY_RATE);
_________________________________________________________________________________________________
18.0 UART and RS-232 Library Module Primer
The “UART and RS-232” communications module supports basic transmission and reception of bytes to and from the
Chameleon PIC serial port. The PIC24HJ has two very advanced UARTs (Universal Asynchronous Serial Receiver and
Transmitters). It is connected directly to the TX/RX pins of the USB FTDI chip which allows serial communication via the
USB port. Additionally, the TX/RX lines can be remapped to any of the PORT B pins so it provides maximum flexibility.
Before we discuss the overall architecture of the UART library module, here are the main features of the PIC24 UART:
As you can see they are pretty powerful and the library API we provide here only scratches the surface of what you can
do with the UART hardware. They can even be used to stream audio or video data if you are really creative since they are
more or less interrupt driven high speed shifting devices. In any event, let’s talk about some preliminary materials before
we begin. You should review the data sheet on the PIC24, especially the USART and also the accompany section of the
PIC24 Reference manual on the UART. The data sheets and reference manual chapter is located here on the DVD:
Finally, the “UART and RS-232” API libraries are contained in the following files:
18.1 The Architecture of the UART API Library and Support Functionality
The UART library is relatively complex in as much as to save you a lot of grief trying to program the PIC UARTs, we
wanted to give you some ready to go software and API functionality, so you could perform basic serial I/O and have some
fun. To that end, we developed a buffered, interrupt driven UART communications system with some moderately powerful
support functions to save you time. Let’s take some time to briefly discuss the overall architecture of the system, so you
know how it’s all put together. This will help understand how the API functions fit together and the data flow of the system.









void SYS_ConfigureClock(unsigned long FCY);
Full Duplex Operation (Independent Serial Receive and Transmit Registers).
high Resolution Baud Rate Generator.
Supports Serial Frames with 8, or 9 Data Bits and 1 or 2 Stop Bits.
Odd or Even Parity Generation and Parity Check Supported by Hardware.
Data Overrun Detection.
Framing Error Detection.
4-deep First-in-First-out (FIFO) Transmit and Receive buffer.
Loopback mode for diagnostic.
IrDA Encoder and Decoder Logic.
DVD-ROM:\ CHAM_PIC \ DOCS \ DATASHEETS \ PIC24HJXXXXGPX06_08_10.pdf
DVD-ROM:\ CHAM_PIC \ DOCS \ DATASHEETS \ Section17-UART.pdf
CHAM_PIC_UART_DRV_V010.c
CHAM_PIC_UART_DRV_V010.h
Configure the clock to the max rate.
SYS_ConfigureClock(…) configures and initializes the PIC24’s PLL register variables to the given clock
rate. Currently only MAX_FCY_RATE is allowed.
- Main C file source for “UART and RS-232” module.
- Header file for “UART and RS-232” module.
© 2009 NURVE NETWORKS LLC “Exploring the Chameleon PIC 16-Bit”
143