Microchip Developer Explorer 16/32 User Manual page 15

Explorer 16/32 Development Board User's Guide - Developer Help
usually be added by recompiling the kernel). Therefore, no additional USB drivers
are normally required.
Upon successful enumeration on a Linux host, the MCP2221A should appear as a
/dev/ttyACMx device (where x is a wildcard that depends on the device instance,
similar to the Windows COMx port number). The specific /dev/ttyACMx name can be
identified by attaching the hardware and from a terminal prompt entering:
lsusb
modprobe cdc-acm vendor=0x04d8 product=0x00dd
dmesg
Once the specific name is known, it can be opened and accessed using a terminal
program such as "GtkTerm".
Using the MCP2221A USB to I C Adapter Functionality
The USB to I C functionality of the MCP2221A can be exercised using the software
tools associated with the MCP2221A (http://www.microchip.com/mcp2221a). When
using the MCP2221A USB to I C functionality to connect with a PIM microcontroller
or accessory board (connected via one of the mikroBUS interfaces or the PICtail Plus
Interface), it is necessary to ensure that jumpers J41 and J42 are both capped.
Other Usage Tips
When using the toggle power switch S7 to power cycle the Explorer 16/32
Development Board, all circuitry on the +5V and +3.3V/VDD_PIM supply rails on the
board will be power cycled, including the MCP2221A.
When using the MCP2221A as a USB-UART serial port device, it is recommended to
always close the serial port (ex: COMx or /dev/tty... device) in the application
software or terminal program, either before, or while the power is still switched off,
prior to restoring power to the board. Similarly, when unplugging the USB
connection to the MCP2221A, always close the serial port, while the cable is
currently unplugged (or even before unplugging the cable), prior to re-attaching the
USB cable.
Failure to follow these procedures can result in the device becoming inaccessible
(especially under Windows OSes prior to Windows 10) following the re-attachment
or re-powering of the device. If this occurs, operation can be restored by performing
the detach or power cycling operation a second time, while making sure to close the
serial port prior to re-attachment/power up.
For best end user experience, when writing application software that may connect to
the serial port, it is recommended to write the application software to be plug and
play aware, so that it can automatically close the serial port as soon as the USB
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7.6.2017 8:59