User manual

PICDEM™ Lab II Development Board User’s Guide
DS40001814A-page 26  2015 Microchip Technology Inc.
4.3 SERIAL/I
2
C COMMUNICATIONS DO NOT WORK
• If the PICDEM Lab II serial interface is not recognized by the ASYNC terminal
program:
- Verify that the serial driver for the MCP2221 is correctly loaded.
- Verify the USB interface cable is firmly seated in the PICDEM Lab II board.
- Verify the USB interface cable is firmly seated in the USB port of the
computer.
- Verify the USB port used is working.
- Verify that power and GND are connected to pins 2 and 3 of J4 and that
voltage is present at the connector.
If the problem persists, contact Microchip’s help line for further assistance.
• If the PICDEM Lab II serial interface is not recognized by the I
2
C/SMBus terminal
program:
- Verify that the I
2
C/SMBus terminal program is correctly loaded.
- Verify the USB interface cable is firmly seated in the PICDEM Lab II board.
- Verify the USB interface cable is firmly seated in the USB port of the
computer.
- Verify the USB port used is working.
- Verify that power and GND are connected to pins 2 and 3 of J4 and that
voltage is present at the connector.
- Verify pull-up resistors are present on the SDA and SCL (pins 4 and 5) lines of J4.
If the problem persists, contact Microchip’s help line for further assistance.