Chameleon-PIC Nurve Networks, Chameleon-PIC Datasheet - Page 254

• 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

Appendix D - Using the PIC in "Stand-Alone" Mode.
The nice thing about the Chameleon is that it’s two systems in one. You are free to use the PIC as you wish and not worry
about the Propeller chip. However, whatever driver that is on the Propeller will run and function independently even
though, you aren’t sending it commands over the SPI channel. Thus, if you truly want to turn off the Propeller, you might
want to load a NULL program that does absolutely nothing such as:
CON
PUB Main
This will start up a single processor, and just sit and do nothing. Of course, without the Propeller, you have no access to
the physical peripheral headers such as the A/V headers, VGA, or the PS/2 header. But, you still have access to the USB
serial port as well as the FLASH memory. And of course, all the headers connected to the PIC around the board you still
have access to. Just make sure to keep the serial select switch in the DOWN position, so the PIC has access to the
USB serial port.
Appendix E - Using the Propeller in "Stand-Alone" Mode.
The Propeller in standalone mode is much more interesting that the PIC. The Propeller in standalone mode allows you to
more or less run anything you would run on a HYDRA or Propeller Development kit still. You have the VGA connector,
PS/2, A/V connectors as well as an 8-bit port for expansion. You might have to do some “porting” of apps since the
HYDRA and Propeller development kits use slightly different pin I/O connections for various devices, but those are literally
1-2 line changes in your code.
The only thing you lose in Propeller stand alone mode is the use of the onboard FLASH since the Propeller can’t get to it,
but the EEPROM for the Propeller is 64K, 2x the amount needed for the boot image, so that’s a conciliation prize in the
design, if you need more assets. Just make sure to keep the serial select switch in the UP position, so the Propeller has
access to the USB serial port.
' These settings are for 5 MHZ XTALS
_clkmode = xtal1 + pll16x
_xinfreq = 5_000_000
repeat ‘ forever loop
' enable external clock and pll times 16
' set frequency to 5 MHZ
© 2009 NURVE NETWORKS LLC “Exploring the Chameleon PIC 16-Bit”
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