SPI set up on stm32 - stm32

i use to set up Display with SPI communication, and i use GPIO Pins CLK, MOSI, RES, DC, CS,
my question is how to set up GPIO_Output pins RES, DC, CS
GPIO Set up
i need to leave default or need to set up pool up?
thank you

For push-pull type output, you don't need the internal pull-up/pull-down.
If you use open-drain output and your board does not have the necessary resistors, you can use the internal pull-up or pull-down, depending on what is required.

Related

STM32 F3 I2C on Port F SCL Push-Pull Failure

We're currently using STM32F373CC micros in several of our designs. Part of our standard design has an EEPROM connected via I2C. We have our own hardware layer that is tried and proven over the decades. However, it relies on the I2C port pins having pull-ups connected externally.
On some of our new designs we have designed out the pull-up on the SCL line and have set the port pin to Push-Pull mode. In theory, this should be no problem. However, what we've found is that the micro seems to be treating the port pin as open-drain regardless of the setting. For this particular design, we're using PF6 and PF7 as SCL and SDA respectively. With no pull-up connected, the SCL line is flat-lined. With internal pull-up enabled, the SCL line is pulsing, but the rise time is so long it's not working.
Nothing in the reference manual or the datasheet says anything about this issue. In the errata sheet we have (V4), there's quite a bit about the GPIO and I2C, but nothing that seems to relate to this.
For what it's worth, I'll copy and paste the relevant bit of the initialisation:
switch( kasPinMap[eSCL].lwI2CNum )
{
case 1: RCC_APB1ENR.I2C1EN = TRUE; nI2CEEpsRegisters = (void*)&I2C1_CR1; break;
case 2: RCC_APB1ENR.I2C2EN = TRUE; nI2CEEpsRegisters = (void*)&I2C2_CR1; break;
}
//configure the pins
DIO_vConfigure( kasPinMap[eSCL].ePort, kasPinMap[eSCL].lwBit, DIOkeM_Alternate, DIOkeD_PushPull, DIOkePU_None, DIOkeSP_Medium, kasPinMap[eSCL].lwAFN );
DIO_vConfigure( kasPinMap[eSDA].ePort, kasPinMap[eSDA].lwBit, DIOkeM_Alternate, DIOkeD_OpenDrain, DIOkePU_None, DIOkeSP_Medium, kasPinMap[eSDA].lwAFN );
//reset and enable the peripheral
nI2CEE_vReset();
In the debugger, GPIOF looks like this:
AFR values are set to 4.
The I2C registers look like this:
And the RCC registers look like this:
Our Technical Director mentioned that to comply with the I2C standard and allow for multi-master mode, both SCL and SDA should both be open-drain. However, all we have here is the F3 and the EEPROM.
Any thoughts on why we might not be getting the push-pull action out of the SCL line would be appreciated.

Can we re-route the DAC output to some other Pins other than PA4 and PA5 in STM32?

I am working with STM32H743, and I want to use Pin no. 89 as DAC output. Is there any register setting where I can change PA4 to PG4(89).
I tried replacing PA4 to PG4 in a working example code, but the output still comes on PA4.
I don't know which STM32F7 you are using exactly so I could not lock at the Reference Manual, but I guess it is the same as on STM32F4 devices:
The answer is quite simple:
NO, you could not reroute the DAC pins.
(A look ad a randomly chosen F7 datasheet also shows only one pin for the DACs)
I simply guess it is not possible to route the output signal through a multiplexer without generating to much interference.
According to the H753 datasheet (can't find a specific one for H743), there are two DAC channels, PA4 is DAC1_OUT1 and PA5 is DAC1_OUT2. It does not appear to be changeable.

LwIP stack add new driver for KSZ8851SNL ethernet controller

Using STM32CubeMX and Atollic TrueStudio, I created a project with a KSZ8851SNL ethernet controller.
On an STM32H742, I have a driver for the Micrel KSZ8851SNL, and created a micro TCP/IP stack, to test the chip. I got that working very well, but it currentl;y only supports ARP, UDP and ICMP. I can ping in two directions, handle ARP request in both directions, and request NTP time from internet.
Now, I would like to let it work together with LwIP.
I know it needs to be implemented in a file ethernetif.c.
Basically, I used these functions to let the micro setup work:
// Initializes the KSZ8851SNL
uint8_t ksz8851_init(void)
// Send a packet, returns length of received package
// The received length can be checked if we received a packet
uint16_t ksz8851_Receive(uint8_t *pRXData, uint16_t pRXMaxLength)
// Receive a packet
void ksz8851_Send(uint8_t *pTXData, uint16_t pTXLength)
The project is an Atollic TrueStudio project, and I use HAL.
Are above functions sufficient for LwIP?
How do I implement this in LwIP?
I read lots of documentation, but it seems not detailed to this part.
Sources are on hithub:
https://github.com/bkht/STM32H7_HAL_KSZ8851SNL
Thanks a lot for helping me out!
One more thing other than uncomment // MX_LWIP_Init();.
I have an STM32H743 Nucleo-144 and tried to run it(commit number f8ff06c2c17f3d6dacbff8c2fd8eb95591a0c224), too. However, it was stuck in this loop: https://github.com/bkht/STM32H7_HAL_KSZ8851SNL/blob/master/Drivers/KSZ8851SNL/Src/KSZ8851SNL.c#L443-L506 because of a failure of reading chip ID with ksz8851_reg_read() . Then I dig deeper in to the source code, and here is a possible solution:
Change the GPIO setting of SPI2's NSS/CS pin
In the .ioc file(if you are still generating workspace with it), set SPI2's "Hardware NSS Signal" to "Hardware NSS Output Signal" in
https://github.com/bkht/STM32H7_HAL_KSZ8851SNL/blob/master/Nucleo-H743ZI_Jack_013_tcp_KSZ8851SNL_Test.ioc.
Or change the source directly by giving PB12 a different GPIO-setting as
GPIO_InitStruct.Pin = GPIO_PIN_12;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_MEDIUM;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_12, GPIO_PIN_SET);
Uncomment the macro of SPI2 CS Pin https://github.com/bkht/STM32H7_HAL_KSZ8851SNL/blob/master/Drivers/KSZ8851SNL/Inc/KSZ8851SNL.h#L55-L67 and the usage of them(// RESET_SPI_CS_PIN(); & // SET_SPI_CS_PIN();) in https://github.com/bkht/STM32H7_HAL_KSZ8851SNL/blob/master/Drivers/KSZ8851SNL/Src/KSZ8851SNL.c
Then, the correct chip ID will be fetched.
Clement

stm32 and external flash (w25q) connection problem

I want to read/write from external flash (Winbond W25Q16BV) with STM32 micro (stm32F030F4). but running process halt on 'HAL_SPI_Init()' function.
I checked the debug process, and found HAL_SPI_STATE_BUSY.
but i don't know why?
I am using STM32CubeMX to generate main project and Keil IDE to write and debug.
SPI_HandleTypeDef hspi1;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_Init(void);
uint8_t spiData[2];
int main(void)
{
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_SPI1_Init();
MX_FATFS_Init();
SPI_HandleTypeDef my_hspi;
HAL_SPI_Init(&my_hspi);
HAL_FLASH_Unlock();
HAL_GPIO_WritePin(GPIOA,GPIO_PIN_1,GPIO_PIN_SET); // CS to HIGH
HAL_Delay(10);
//Read data
HAL_GPIO_WritePin(GPIOA,GPIO_PIN_1,GPIO_PIN_RESET); // CS to low
spiData[0]=0x05;
//transmit register address
HAL_SPI_Transmit(&my_hspi,spiData,1,10);
//read
HAL_SPI_Receive(&my_hspi,&spiData[1],1,10);
...
Here is our schematic:
Unfortunately, I did not find a good example/instruction of how to use external SPI libraries. Any help in this problem is highly appreciated.
I am not able to comment on the software, but according to your comment you want to enable the reading and writing of the flash.
The Write Protect (/WP) pin can be used to prevent the Status Register from being written.
The /WP pin is active low (GND). (Write disable)
The /WP pin is inactive high (VCC). (Write enable)
Its design only allows reading data.
If you want to read and write data, /WP must be connected to Vcc.
You have not set any parameters for the my_hspi struct so your HAL driver doesn't know what he has to do.
Look at the definition of the struct. There are a lot of comments what the different struct elements are used for. For initialization the my_hspi.init part will be most interesting.
Also you have to the the my_hspi.Instance to the desired SPI Channel.
You can generate an example configuration using the free STM32 Cube Mx Software.

Does GPIO Linux framework support to change mode between GPIO and IRQ

I checked the sysfs of GPIO, it only supports to configure the direction (in, out), active_level, edge.
I don't see it supports to change mode between GPIO and interrupt. Do any you know it ? Or any suggest.
Example:
Some GPIOs can supports either GPIO or IRQ. So I would like to change mode it under Linux via sysfs.
Thanks in advance.
The GPIO controller (and thus driver) will provide that support if any. In that case GPIO controller is registered as an interrupt controller. There are a lot of examples, like gpio-intel-mid.c where you have:
retval = gpiochip_irqchip_add(&priv->chip,
&intel_mid_irqchip,
irq_base,
handle_simple_irq,
IRQ_TYPE_NONE);
if (retval) {
dev_err(&pdev->dev,
"could not connect irqchip to gpiochip\n");
return retval;
}