usb device cdc sample can not send 512byte

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
Us16_3774766
Level 1
Level 1
First like received First like given

I am checking USB Device CDC funciton on CWY943907AEVAL1F. I use WICED-Studio-6.2.

I modified the snip.usbx_usb_device.usb_device_cdc_acm_read_write to send data from device to host.

I called  ux_device_class_cdc_acm_write function like below.

I connected the device to PC(USB Host).

The case '1' is OK, but in  case '2'  the transmission is not done as expected.

Is there a limit on the size of one transmission?

'1'     

for (int i = 0; i < 1000; i++) {

     ux_device_class_cdc_acm_write( cdc_acm, tempbuf, 256, &actual_length );     // OK

}

'2' 

for (int i = 0; i < 1000; i++) {

     ux_device_class_cdc_acm_write( cdc_acm, tempbuf, 512, &actual_length );     // NG

}

'3' 

for (int i = 0; i < 1000; i++) {

     ux_device_class_cdc_acm_write( cdc_acm, tempbuf, 511, &actual_length );     // OK

}

0 Likes
1 Solution
PriyaM_16
Moderator
Moderator
Moderator
250 replies posted 100 replies posted 50 replies posted

Hello Sir,

This is a known issue in WICED which will be fixed in the next release. I will update the thread when the fix is available.

View solution in original post

2 Replies
PriyaM_16
Moderator
Moderator
Moderator
250 replies posted 100 replies posted 50 replies posted

Hello Sir,

This is a known issue in WICED which will be fixed in the next release. I will update the thread when the fix is available.

Thank you for your information.

I ’m looking forward to updating WICED.

0 Likes