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FLEX Board USB connection without demo board

The demo board provide correct SPI connection between the PIC18 and the dsPIC. If you are not using the demo board you can set-up manually a SPI connection. For safety considerations it is STRONGLY recommended to use the same voltage for both dsPIC and PIC18, 3.3V. In the following figure you can be see SPI connections and jumpers setttings.

In the USB applications note the PIC18 is only a transceiver since it receives messages from the host PC through a USB connection and forwards these messages to the dsPIC through a SPI connection. The PIC18 has a full speed USB 2.0 interface that allows to easily implement USB connection with host computers. The PIC18 can be only a device. We used the code furnished by Microchip to implement the HID behaviour of the PIC18.

You can have PIC18 firmware for USB applications downloading the scicoslab pack: http://erika.tuxfamily.org/scilabscicos.html

Application reference: http://erika.tuxfamily.org/wiki/index.php?title=USB_communication_using_FLEX_FULL_Demo_Board_and_the_Scilab/Scicos_code_generator

This is a list of the peripherals currently used in the EE device drivers for the FLEX boards:

Note: the list is currently incomplete!