Nucleo-144 F439ZI : OTG in FS Mode with DMA does not enumerate

[FabriceG]

Hi everyone,

I'm trying to use OTG in FS Mode with DMA enabled (I know it's not a consistent use case, as FS datarate is pretty low)

But still, I changed the code in Drivers\STM32F4xx_HAL_Driver\Src\stm32f4xx_hal_pcd.c :

...

#if defined (USB_OTG_FS)
/* Disable DMA mode for FS instance */
if (USBx == USB_OTG_FS)
{
    hpcd->Init.dma_enable = ENABLE; //FGE: try to use OTG FS with DMA enabled
}
#endif /* defined (USB_OTG_FS) */

...

But it does not enumerate. 

This is the only change I brought to the CubeMX generated code

Any hints ?

Thanks

Fabrice

[FBL]

Hello @FabriceG 

Do you reproduce when starting with this reference example?

[waclawek.jan]

Make sure that any data buffer you allocate in RAM and try to reach using the OTG's DMA is NOT in the CCMRAM.

JW

[AScha.3]

Hi,

>trying to use OTG in FS Mode

but no info, what you wanna do at all : host : for ...?  , device : for ...?  and dma , because ...?

+

> But it does not enumerate. 

Who should enumerate ...? as a ...?

[FabriceG]

I'm using HID profile

[FBL · Accepted solution]

Hi @FabriceG 

This is not the proper way to test USB DMA (by  modifying drivers). As I suggested, you can refer to the example and enable DMA in the initialization. You can refer directly here; I've tested it on my end and it's working as expected.

[FabriceG]

Thanks FBL, it's clear now.