Dear @HFISTM ,
I'm debbuging the hell out of this aplication, and the problem seems to be within line 432 of usbpd_user_services.c file. The USER_SERV_SNK_EvaluateMatchWithSRCPDO function passes only the max possible voltage to the RequestedVoltage variable used in ResquestMessageRequest function, then causing its if condition of equality between voltage and RequestedVoltage to be False, which then traces the Debug message "REQUEST not accepted by the stack". I just don't know what value to use on line 432 for it to proceed in the right way.
After commenting out this line, the application seems to be out of control, as it won't establish a contract. The hardware it keeps unstoppably requesting for the APDO to be instated, rejecting the request and then resetting, over and over.
Here you can see one iteration of this unending cycle of madness:
Regards,
Felipe
Its not relevant yet for you but I hope someone will find this answer useful. The VBUS_Get_Current() function example can be found in CubeMX examples for G0 boards: STM32G081B-EVAL. You need to open the DemoUCPD project in CubeIDE, for me the path is:
C:\ST\STM32CubeMX\Repository\STM32Cube_FW_G0_V1.6.2\Projects\STM32G081B-EVAL\Demonstrations\DemoUCPD
Now in DemoUCPD\Src\demo_application.c you can find the BSP_USBPD_PWR_VBUSGetCurrent() call which can lead you to the example when looking for its declaration.
/**
* @brief Get actual current level measured on the VBUS line.
* @PAram Instance Type-C port identifier
* This parameter can be take one of the following values:
* @arg @ref USBPD_PWR_TYPE_C_PORT_1
* @arg @ref USBPD_PWR_TYPE_C_PORT_2
* @PAram pCurrent Pointer on measured current level (in mA)
* @retval BSP status
*/
int32_t BSP_USBPD_PWR_VBUSGetCurrent(uint32_t Instance, int32_t *pCurrent)
{
/* USER CODE BEGIN BSP_USBPD_PWR_VBUSGetCurrent */
/* Check if instance is valid */
int32_t ret = BSP_ERROR_NONE;
if ((Instance >= USBPD_PWR_INSTANCES_NBR) || (NULL == pCurrent))
{
ret = BSP_ERROR_WRONG_PARAM;
}
else
{
int32_t current = 0;
if (Instance == USBPD_PWR_TYPE_C_PORT_1)
{
current = PWR_ConvertADCDataToCurrent(aADCxConvertedValues[2u]);
}
else
{
if (Instance == USBPD_PWR_TYPE_C_PORT_2)
{
current = PWR_ConvertADCDataToCurrent(aADCxConvertedValues[3u]);
}
}
*pCurrent = current;
}
return ret;
/* USER CODE END BSP_USBPD_PWR_VBUSGetCurrent *//**
* @brief Calculate the VBUS current level corresponding to ADC raw converted data.
* @note Current level is measured though INA199x1 output voltage level.
* @note INA199x1 measures currents through a resistive shunt (0.005 Ohms) in
* two directions.
* @note VDD corresponds to the zero-input level state. The Vout responds
* by increasing above VDD for positive differential signals (relative
* to the IN� pin) and responds by decreasing below VDD for negative
* differential signals.
*
* VBUS -----. Rs .-....
* | | .------------.
* | | | INA199x1 |
* | | | |
* | '--> IN+ > Vout (GAIN * Vs)
* | Vs ^ | | 0 <= Vout < VDD - negative current
* | | | | Vout = VDD - zero-input
* '-------> IN- | Vout > VDD - positive current
* | |
* Vref > |
* (Vdd/2) | |
* '------------'
*
* Is = Vout/(GAIN * Rs) = (Vout - 2*Vref)/(Gain * Rs)
* where Vout = ADCData * (VDD/ADC_FULL_SCALE)
* Is = (ADCData * Vdd)/(ADC_FULL_SCALE * Gain * Rs) - Vdd/(Gain * Rs)
* Vdd = 3300 mV, ADC_FULL_SCALE = 4095, Gain = 50, Rs = 5/1000
* @PAram ADCData ADC raw converted data (resolution 12 bits)
* @retval VBUS analog current (unit: mA)
*/
static int32_t PWR_ConvertADCDataToCurrent(uint32_t ADCData)
{
int32_t current;
current = ((ADCData * VDD) >> 10u) - 6600u;
return current;
}Note that the Current measurement on STM32G081B-EVAL is provided by UCPD daughterboard USB PD and its INA199C1DCKR (see Figure 50. in UM2403).
Isense measurement is also native for TCPP02 and TCPP03 with using small R (as in Figure 14. of UM2891), but not for TCPP01 (which is on SNK1M1).
