VCP driver without SOF output?

[pa_it]

Posted on October 23, 2013 at 17:22

Hi all

I've a little problem. I use the USB driver from st to communicate with my STM32F4-Discovery. This works realy good. But I've would make a streaming protocol with a camera sensor. For this I have to use the MCO1. The parts works but in combination it won't do anything. So I searched for a reason. Then I've found something special in the driver library:

The SOF overwrites the MCO1 configuration from PA8, but this pin isn't used for anything. If I remove the PA8 configuration for SOF output, the usb doesn't work correctly.

So for what is this pin used? Is ist also used internal for something?

Best regards

Patrick

[Tesla DeLorean]

Posted on October 23, 2013 at 18:10

It's connected internally to TIM2

Which VCP example are you using?

Neither of these need to be defined

  USB_OTG_HS_SOF_OUTPUT_ENABLED

  USB_OTG_FS_SOF_OUTPUT_ENABLED

> OTG_FS_GCCFG - SOFOUTEN

Are you saying the GPIO_PinAFConfig(GPIOA, GPIO_PinSource8, GPIO_AF_MCO) setting doesn't stop SOF emanating from PA8?

[pa_it]

Posted on October 23, 2013 at 18:31

I can't say which example it is. I know the author: MCD application team.

The output-enalbe isn't defined so normaly there wouldn't be any output. But in the usb_bsp.c with the Port init function the SOF pin is configured as GPIO_AF_OTG1_FS.

if
(DCMI_OV9655Config()){
// Enable DMA transfer
DMA_Cmd(DMA2_Stream1, ENABLE);
// Enable DCMI interface
DCMI_Cmd(ENABLE);
Delay_ms(100);
// Start Image capture
DCMI_CaptureCmd(ENABLE);
STM_EVAL_LEDOn(LED3);
}
USBD_Init(&USB_OTG_dev, 
// OTG core handle
USB_OTG_FS_CORE_ID, 
// OTG core id
&USR_desc, 
// USB descriptors
&USBD_CDC_cb, 
// CDC callback
&USR_cb); 
// User callback


/* Configure SOF VBUS ID DM DP Pins */
/* 

* Configure USB Pins
* SOF PA8 Start of frame
* VBUS_FS PA9 Vbus
* OTG_FS_ID PA10 ID
* OTG_FS_DM PA11 DM
* OTG_FS_DP PA12 DP
*
*/
GPIO_InitStructure.GPIO_Pin = 
/*GPIO_Pin_8 | */
GPIO_Pin_9 | GPIO_Pin_11 | GPIO_Pin_12;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
GPIO_Init(GPIOA, &GPIO_InitStructure); 
// GPIO_PinAFConfig(GPIOA,GPIO_PinSource8,GPIO_AF_OTG1_FS) ;
GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_OTG1_FS) ; 
GPIO_PinAFConfig(GPIOA,GPIO_PinSource11,GPIO_AF_OTG1_FS) ; 
GPIO_PinAFConfig(GPIOA,GPIO_PinSource12,GPIO_AF_OTG1_FS) ;
/* this for ID line debug */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ; 
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure); 
GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_OTG1_FS) ; 

The PA8 configuration for MCO1 output in DCMI init is overwritten from USB init, but the dont work together.

USB GPIO Init part: Uncomment PA8 configuration and the driver doesn't work

[Tesla DeLorean]

Posted on October 23, 2013 at 19:12

Seem to be able to emit 8 MHz via PA1/MCO1 without issue on my VCP build based on STM32_USB-Host-Device_Lib_V2.1.0\Project\USB_Device_Examples\VCP

[pa_it]

Posted on October 24, 2013 at 18:41

I've found something spetial:

After the camera init (dcmi with dma) a hard-fault exception occours. But only if both are used (camera and vcp). Then I've checked core registers:

r0 536950144 
r1 536909696 
r2 10 
r3 58 
r12 276959362 
lr 0 
pc 134220219 
psr 134220184 

The programm counter is locatet nearly USB_OTG_IsDeviceMode in usb_core.c (the address doesn't exist in my disassebly window). But there is something else: The lr is 0. How could thes be?

[Tesla DeLorean]

Posted on October 24, 2013 at 18:54

The lr is 0. How could this be?

The DMA transfer nuked the stack?

[pa_it]

Posted on October 24, 2013 at 19:56

What could be the reason? Is the dma using the stack? And for what?

[Tesla DeLorean]

Posted on October 24, 2013 at 20:53

I know as much about your software as you've told me.

The DMA operates autonomously of the processor, if your video signal is being written over the stack, you could see odd values in registers, including LR. Why would you point it at the stack? Perhaps you don't think you are, but then again the data you are requesting is also very large and it's not inconceivable you could overwrite things if your buffers are too small, or programmed incorrectly into the DMA controller.

Is your stack adequately sized? Again if you mess up the stack the processor context could well get fouled up.

[pa_it]

Posted on October 25, 2013 at 17:25

Here is the camera initialization:

volatile uint16_t DCMI_Buffer[160 * 120] = {0};
void DCMI_Config(void)
{
DCMI_InitTypeDef DCMI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable DCMI GPIOs clocks */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_GPIOB |
RCC_AHB1Periph_GPIOC | RCC_AHB1Periph_GPIOE, ENABLE);
/* Connect DCMI pins to AF13 ************************************************/
GPIO_PinAFConfig(GPIOA, GPIO_PinSource4, GPIO_AF_DCMI); 
// DCMI_HSYNC
GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_DCMI); 
// DCMI_PIXCK
GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_DCMI); 
// DCMI_VSYNC
GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_DCMI); 
// DCMI_D0
GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_DCMI); 
// DCMI_D1
GPIO_PinAFConfig(GPIOC, GPIO_PinSource8, GPIO_AF_DCMI); 
// DCMI_D2
GPIO_PinAFConfig(GPIOC, GPIO_PinSource9, GPIO_AF_DCMI); 
// DCMI_D3
GPIO_PinAFConfig(GPIOC, GPIO_PinSource11, GPIO_AF_DCMI); 
// DCMI_D4
GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_DCMI); 
// DCMI_D5
GPIO_PinAFConfig(GPIOE, GPIO_PinSource5, GPIO_AF_DCMI); 
// DCMI_D6
GPIO_PinAFConfig(GPIOE, GPIO_PinSource6, GPIO_AF_DCMI); 
// DCMI_D7
/* DCMI GPIO configuration **************************************************/
/* HSYNC(PA4), PCLK(PA6) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 | GPIO_Pin_6;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* VSYNC(PB7), D5(PB6) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_Init(GPIOB, &GPIO_InitStructure);
/* D0(PC6), D1(PC7), D2(PC8), D3(PC9), D4(PC11) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7 | GPIO_Pin_8
| GPIO_Pin_9 | GPIO_Pin_11;
GPIO_Init(GPIOC, &GPIO_InitStructure);
/* D6(PE5), D7(PE6) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6;
GPIO_Init(GPIOE, &GPIO_InitStructure);
/* DCMI configuration *******************************************************/
/* Enable DCMI clock */
RCC_AHB2PeriphClockCmd(RCC_AHB2Periph_DCMI, ENABLE);
// Reinitialize
DCMI_DeInit();
DCMI_InitStructure.DCMI_CaptureMode = DCMI_CaptureMode_Continuous;
DCMI_InitStructure.DCMI_SynchroMode = DCMI_SynchroMode_Hardware;
DCMI_InitStructure.DCMI_PCKPolarity = DCMI_PCKPolarity_Falling;
DCMI_InitStructure.DCMI_VSPolarity = DCMI_VSPolarity_High;
DCMI_InitStructure.DCMI_HSPolarity = DCMI_HSPolarity_High;
DCMI_InitStructure.DCMI_CaptureRate = DCMI_CaptureRate_All_Frame;
DCMI_InitStructure.DCMI_ExtendedDataMode = DCMI_ExtendedDataMode_8b;
DCMI_Init(&DCMI_InitStructure);
/* DCMI Interrupts config ***************************************************/
// DCMI_ITConfig(DCMI_IT_VSYNC, ENABLE);
// DCMI_ITConfig(DCMI_IT_LINE, ENABLE);
DCMI_ITConfig(DCMI_IT_FRAME, ENABLE);
// DCMI_ITConfig(DCMI_IT_ERR, ENABLE);
// DCMI_ITConfig(DCMI_IT_OVF, ENABLE);
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
NVIC_InitStructure.NVIC_IRQChannel = DCMI_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Configures the DMA2 to transfer Data from DCMI to the LCD ****************/
/* Enable DMA2 clock */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
/* DMA2 Stream1 Configuration */
DMA_Cmd(DMA2_Stream1, DISABLE);
DMA_DeInit(DMA2_Stream1);
while
(DMA_GetCmdStatus(DMA2_Stream1) != DISABLE); 
// Check if the DMA Stream is disabled before enabling it.
DMA_InitStructure.DMA_Channel = DMA_Channel_1;
DMA_InitStructure.DMA_PeripheralBaseAddr = DCMI_DR_ADDRESS;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)DCMI_Buffer;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
DMA_InitStructure.DMA_BufferSize = (160 * 120);
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Enable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA2_Stream1, &DMA_InitStructure);
}
void MCO1_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
// Enable GPIOs clocks
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
// Configure MCO (PA8)
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; 
GPIO_Init(GPIOA, &GPIO_InitStructure);
RCC_MCO1Config(RCC_MCO1Source_HSI, RCC_MCO1Div_1);
}

the stack size is defined as following: #define STACK_SIZE 0x00002000 /*!< Stack size (in Words) I have no idea where the dma crashes the stack...

[pa_it]

Posted on October 25, 2013 at 17:26

Could there be a problem with the usb interrupts or something else?

[Tesla DeLorean]

Posted on October 25, 2013 at 17:42

Could there be a problem with the usb interrupts or something else?

There could be problems in all manner of aspects, you'll have to start with the Hard Fault in the debugger and dig from there. Break point the Hard Fault, inspect the registers and stacks, look at memory and try to pin point why/how it got there.