Chameleon-AVR Nurve Networks, Chameleon-AVR Datasheet - Page 35

• Manufacturer Part Number: Chameleon-AVR
• Description: MCU, MPU & DSP Development Tools AVR8 & PROPELLER DEV SYSTEM (SBC)
• Manufacturer: Nurve Networks

Specifications of Chameleon-AVR

• Processor To Be Evaluated: AVR 328P
• Data Bus Width: 8 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

© 2009 NURVE NETWORKS LLC “Exploring the Chameleon AVR 8-Bit”
8.0 Parallax Propeller Subsystem
Figure 8.1 – The Propeller Subsystem.
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Figure 8.1 depicts the entire Propeller chip subsystem. It consists of the Propeller chip itself (QFP package), the 64K I
C
serial EEPROM for program storage, a single LED, and the Propeller Port I/O header at J8. Additionally, the Propeller is
clocked by a 5 MHz nominal XTAL at X1. The only thing interesting about the design is the free Propeller Local Port at J8,
it connects to Propeller I/O pins P0…P7. Thus, you can connect other devices to this header, or potentially drive another
NTSC/PAL/VGA video device or you can just use it at 8 more digital I/O ports. Lastly, the Propeller chip only needs a 32K
EEPROM to load its runtime image into its local SRAM, however, we are using a 64K EEPROM which not only allows 2
images, but potentially a single image with additional program assets like graphics, sound, or code.
8.1 The Propeller Local 8-Bit I/O Port
The Propeller Local Port is an 8-bit port consisting of 8 free digital I/O pins from P0…P7 on the Propeller chip. You can do
anything you want with the port. You can even power devices from the port by using some of the pins as power and virtual
ground. The Propeller can source up to 40mA per pin, so if you tie 2 lines together and set them HIGH, you can source up
to 80mA, more than enough for most applications.
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