i.MX Processorsのトピックusb problem

usb problem

eao — Thu, 23 Feb 2023 01:24:35 GMT

Hello, official website staff, I found a problem in imxrt1170 platform, in board_usb_device.c, line 350, function
usb_DeviceCdcAcmRecv(handle, USB_CDC__VCOM_BULK_OUT_ENDPOINT, s_currRecvBuf, g_UsbDeviceCdcVcomDicEndpoint[1].maxPackrtSize), the last one in maxpacketsize parameter, I seem to be able to modify its size, I will modify it to 2048, the usb can still be normal, but once I modify it to 10000, it seems to communicate abnormal, please ask This is why? Thanks!

Re: usb problem

jingpan — Mon, 27 Feb 2023 06:55:21 GMT

Hi @eao ,

USB FS bulk transfer maximum size is 64. USB HS bulk transfer maximum size is 512.

Regards,

Jing

Re: usb problem

eao — Thu, 02 Mar 2023 05:35:04 GMT

thanks!
I would like to ask a question, in the official example of usb, "dev_cdc_vcom_bm_cm7" is used as a slave device and the computer is used as the master device to send data to the development board, I found that multiple interrupts are generated and each interrupt has 512 bytes, is there an example of this? Is there any example where only one interrupt can be generated and all data will be received? Thanks!

Re: usb problem

jingpan — Mon, 06 Mar 2023 03:18:29 GMT

Hi @eao ,

Sorry I don't understand what you mean. CDC example use 2 endpoint, one bulk in and one bulk out. There isn't examples use only one interrupt to send all data.

Regards,

jing