USBD_PHDC_WrCfg

Owned by Former user (Deleted)
Last updated: Dec 03, 2020 by WES Admin
2 min read

Description

Initialize write communication pipe parameters.

Files

usbd_phdc.h / usbd_phdc.c

Prototype

void  USBD_PHDC_WrCfg (CPU_INT08U           class_nbr,
                       LATENCY_RELY_FLAGS   latency_rely,
                       CPU_INT08U          *p_data_opaque,
                       CPU_INT08U           data_opaque_len,
                       USBD_ERR            *p_err);


Arguments

class_nbr

PHDC instance number.

latency_rely

Bitmap of transfer Latency / reliability that this communication pipe will carry. Can be one or more of these values:

USBD_PHDC_LATENCY_VERYHIGH_RELY_BEST
USBD_PHDC_LATENCY_HIGH_RELY_BEST
USBD_PHDC_LATENCY_MEDIUM_RELY_BEST
USBD_PHDC_LATENCY_MEDIUM_RELY_BETTER
USBD_PHDC_LATENCY_MEDIUM_RELY_GOOD
USBD_PHDC_LATENCY_LOW_RELY_GOOD

p_data_opaque

Pointer to a buffer that contains opaque data related to this communication pipe.

data_opaque_len

Length of opaque data (in octets). If 0, no metadata descriptor will be written for the endpoint.

p_err

Pointer to variable that will receive the return error code from this function.

USBD_ERR_NONE
USBD_ERR_NULL_PTR
USBD_ERR_INVALID_ARG

Returned Value

None.

Callers

Application.

Notes / Warnings

  1. USBD_PHDC_WrCfg() should be called after USBD_PHDC_Init and USBD_PHDC_Add but before USBD_PHDC_CfgAdd().
  2. Since low latency transfers will use a different endpoint, it is possible to set different opaque data for that endpoint. In case the application need different opaque data for low latency pipe, USBD_PHDC_WrCfg() should be called twice. Once with all the desired latency/reliability flags set except for low latency, opaque data passed at this call will be used for the Bulk endpoint metadata descriptor. USBD_PHDC_WrCfg() should then be called once again with only the low latency flag set, opaque data passed at this call will be used for interrupt endpoint metadata descriptor.