Configuration Options

Set the system configuration options in the file src/config/config_usbh_lms.h. This section lists the available configuration options and their default values.


The device type. Select from the possible values in the file api_usbh_lms.h. The default is LMS_CHIP_TYPE_TM4C1294.


The stack size of the transfer task(s). The default is 1024.


The ISR ID of the host controller. The default is INT_USB0.


The ISR priority of the host controller. The default is configKERNEL_INTERRUPT_PRIORITY.


The maximum number of host channels that can be assigned to endpoints, excluding EP0s. The default is 14.

The actual number depends on the USB core implementation used. Usually this number of channels cannot be distributed between all connected devices' endpoints freely, but the the same number of IN (Host Rx) and OUT (Host Tx) endpoints is available. Consult the MCU's data sheet for the actual number of available channels.

Some example chip implementations are shown below:

Device IN and OUT endpoints
LM3S3748, LM3S3749, LM3S3768 3 IN + 3 OUT
TM4C1294 7 IN + 7 OUT
LM3S9B92, LM3S9D92, LM3S9B96 15 IN + 15 OUT


The maximum number of Bulk and Interrupt endpoints, including EP0s. The default is 5.