How I2C address mapping done with internal I2C_SLAVE macro? - i2c

In ioctl call below, why must I pass I2C_SLAVE as the second argument if I pass the I2C address in third argument?
#define I2C_SLAVE 0x0703 /* Use this slave address */
...
int addr = 0x40; /* The I2C address */
...
if (ioctl(file, I2C_SLAVE, addr) < 0) { ... }

Related

EEPROM emulator on STM32L053

I known that isn't normal to use EEPROM emulator on a STM32L053, because it has is own EEPROM, but nowadays with the chip shortage, i was forcedto use an alternative MCU (STM32L053R8T6) instead of the "original design" (STM32F030C8T6), so i want to use the same code for both MCU, so the EEPROM emulator on the STM32L053R8T6.
But i'm having some difficulty using the EEPROM emulator on the STM32L053, the compiler didn't give any error, and the code run normmally, but didn't save any value to the EEPROM.
Header File:
#define ADDR_FLASH_PAGE_60 ((uint32_t)0x0800F000) /* Base # of Page 60, 1 Kbytes */
#define ADDR_FLASH_PAGE_61 ((uint32_t)0x0800F400) /* Base # of Page 61, 1 Kbytes */
#define ADDR_FLASH_PAGE_62 ((uint32_t)0x0800F800) /* Base # of Page 62, 1 Kbytes */
/* Define the size of the sectors to be used */
#define PAGE_SIZE (uint32_t) FLASH_PAGE_SIZE /* Page size */
/* EEPROM start address in Flash */
#define EEPROM_START_ADDRESS ((uint32_t) ADDR_FLASH_PAGE_60) /* EEPROM emulation start address */
/* Pages 0 and 1 base and end addresses */
#define PAGE0_BASE_ADDRESS ((uint32_t)(EEPROM_START_ADDRESS + 0x0000))
#define PAGE0_END_ADDRESS ((uint32_t)(EEPROM_START_ADDRESS + (PAGE_SIZE - 1)))
#define PAGE1_BASE_ADDRESS ((uint32_t)(ADDR_FLASH_PAGE_61))
#define PAGE1_END_ADDRESS ((uint32_t)(ADDR_FLASH_PAGE_61 + PAGE_SIZE - 1))
/* Used Flash pages for EEPROM emulation */
#define PAGE0 ((uint16_t) 0x0000)
#define PAGE1 ((uint16_t)((PAGE1_BASE_ADDRESS-PAGE0_BASE_ADDRESS)/PAGE_SIZE)) /* Virtual page nb between PAGE0_BASE_ADDRESS & PAGE1_BASE_ADDRESS*/
/* No valid page define */
#define NO_VALID_PAGE ((uint16_t)0x00AB)
/* Page status definitions */
#define ERASED ((uint16_t)0xFFFF) /* Page is empty */
#define RECEIVE_DATA ((uint16_t)0xEEEE) /* Page is marked to receive data */
#define VALID_PAGE ((uint16_t)0x0000) /* Page containing valid data */
/* Valid pages in read and write defines */
#define READ_FROM_VALID_PAGE ((uint8_t)0x00)
#define WRITE_IN_VALID_PAGE ((uint8_t)0x01)
/* Page full define */
#define PAGE_FULL ((uint8_t)0x80)
void EE_ReadData(void);
uint16_t EE_Init(void);
uint16_t EE_ReadVariable(uint16_t VirtAddress, uint16_t* Data);
uint16_t EE_WriteVariable(uint16_t VirtAddress, uint16_t Data);
#endif /* __EEPROM_H */
EEPROM Write Variable Function:
uint16_t EE_WriteVariable(uint16_t VirtAddress, uint16_t Data)
{
uint16_t Status = 0;
/* Write the variable virtual address and value in the EEPROM */
Status = EE_VerifyPageFullWriteVariable(VirtAddress, Data);
/* In case the EEPROM active page is full */
if (Status == PAGE_FULL)
{
/* Perform Page transfer */
Status = EE_PageTransfer(VirtAddress, Data);
}
/* Return last operation status */
return Status;
}

STM32 UART multiprocessor mode with address mark detection. Intended data bytes are interpreted as address bytes

I have configured the UART for multiprocessor communication over RS485. I can receive and transmit data correctly. After waking up (RWU=0) when the correct address is received subsequent bytes should be received normally, and not interpreted as another address is my understanding. But if the intended data bytes contains a '1' as MSB it is interpreted as an address. Now it is clear from the documentation that this is the correct behavior, but after the correct address is received (RWU set to 0 and RXNE set to 1, confirmed by debugging) I can only receive data with a value less than the defined address. For example, if I set wordlength to 9bit and the address to 4, the correct address will be 132 (10000100) which is expected (address length is 8 bit in this case I think, because ADDM7 is set). But subsequent bytes are still interpreted as addresses. Sending 132,55,45,150 (via RealTerm) will only receive 132,55,45 as 132 is the correct address and 44,55 has '0' as MSB. 150 is interpreted as a new address because of the '1' in the MSB and RWU is again set to 1 since it is the incorrect address and I can no longer receive data.
My question is how can i interpret subsequent bytes after an correct address as pure data bytes, before I go back to listening for an address again? If I understand correctly, RWU and RXNE is set by HW in this mode? Or is there something specific I should do in FW? My implementation is interrupt-based for now.
The MCU I use is F303K8.
I'll attach some pictures, code and documentation for details and clarity.
Thanks!
Reference manual:
Code and debug:
int main(void)
{
/* USER CODE BEGIN 1 */
testvar = testvar + 1;
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_USART1_UART_Init();
/* USER CODE BEGIN 2 */
HAL_UART_Transmit(&huart1, (uint8_t*)test, strlen(test), 100);
HAL_MultiProcessor_EnableMuteMode(&huart1);
HAL_MultiProcessor_EnterMuteMode(&huart1);
/* Listen for address */
if(HAL_UART_Receive_IT(&huart1, (uint8_t*)rx_buffer, BUFSIZE) != HAL_OK){
Error_Handler();
}
//HAL_MultiProcessor_EnterMuteMode(&huart1);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
//HAL_Delay(500);
//testvar = testvar + 1;
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
//testvar = 64;
/* ADDRESS received! Begin listening for data(COMMANDS)
* When CMDs handled, enter mute mode again in order to listen for address byte again */
if(HAL_UART_Receive_IT(&huart1, (uint8_t*)rx_buffer, BUFSIZE) != HAL_OK){
Error_Handler();
}
}
Oscilloscope:

Port Expander Read via i2c in uboot

I have a customized hardware with a port expander (PCA9555) that is connected via i2c to my SOM. The port expander is on bus 2 and is device 23. Now I need to read the value of Port P0 in a part of the u-boot environment. So i need to use the i2c commands. I have the following code but i can first test it on the hardware on Monday so my question is if somebody uses the same port expander and can tell me if my code is correct?! Thanks
const int bus = 2;
const int device = 0x23;
int ret = i2c_set_bus_num(bus);
if (ret) {
return 0;
}
ret = i2c_probe(device);
if (!ret) {
uint8_t value;
i2c_read(0x23, 0x00, 1, &value, 1);
}

Not able to read from an external EEPROM using the STM32F103C8

I'm trying to write and read from an external EEPROM. There is a start bit (SB) followed by an opcode, then a 6-bit address and then the actual data. I've combined the SB and opcode into one byte that I can send as a start condition. I'm able to enable, erase and then write to the EEPROM. I'm assuming this is working since the HAL functions return HAL_OK and I can see the valid waveforms on the scope.
What I can't seem to do is read the data back. For the READ operation I don't see any waveforms on the scope. The number of clock cycles required is odd-numbered and not in multiples of 8. I don't know how I can send odd number of clock cycles since all the data is either 8, 16 or 32-bit. Wherever there are 25 or 29 clock cycles need, I seem to be sending 32 and where the required cycles are 9, I seem to be sending 16. I'm really hoping to avoid bit-banging as suggested in this thread.
Here is the main code:
int main(void)
{
HAL_Init();
MX_GPIO_Init();
MX_SPI1_Init();
__HAL_SPI_ENABLE(&hspi1);
// pull the CS pin high to select the EEPROM (active HIGH)
HAL_GPIO_WritePin(CS_GPIO_Port, CS_Pin, GPIO_PIN_SET);
HAL_Delay(10);
// Enable the EEPROM
enable_status = Enable_EEPROM(&EEPROM_SPI_PORT);
HAL_Delay(10);
// Erase the value at address 0x00
erase_status = Erase_EEPROM(&EEPROM_SPI_PORT, addr);
HAL_Delay(10);
// Write data 0xABCD at addr 0x00
write_status = Write_EEPROM(&EEPROM_SPI_PORT, addr, tx_data);
HAL_Delay(10);
// Disabling the EEPROM (with an EWDS) after a WRITE as described in the datasheet
disable_status = Disable_EEPROM(&EEPROM_SPI_PORT);
HAL_Delay(10);
// Re-enabling it
enable_status = Enable_EEPROM(&EEPROM_SPI_PORT);
HAL_Delay(10);
// Read from the EEPROM. This part isn't working.
read_status = Read_EEPROM(&EEPROM_SPI_PORT, addr, rx_data);
HAL_Delay(10);
// Pull the CS pin low to deselect the chip again.
HAL_GPIO_WritePin(CS_GPIO_Port, CS_Pin, GPIO_PIN_RESET);
while (1)
{
}
}
The SPI is initialized to handle 16-bit data values
SPI_HandleTypeDef hspi1;
/* SPI1 init function */
void MX_SPI1_Init(void)
{
hspi1.Instance = SPI1;
hspi1.Init.Mode = SPI_MODE_MASTER;
hspi1.Init.Direction = SPI_DIRECTION_2LINES;
hspi1.Init.DataSize = SPI_DATASIZE_16BIT;
hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
hspi1.Init.NSS = SPI_NSS_SOFT;
hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_64;
hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi1.Init.CRCPolynomial = 10;
if (HAL_SPI_Init(&hspi1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
}
These are the EEPROM functions
#define ERASE 0x07 // erase specific memory location. This is followed by the 8-bit address and then by the 16-bit data.
#define READ 0x06 // read the memory location.
#define WRITE 0x05 // write to the memory location
#define EEPROM_SPI_PORT hspi1
extern SPI_HandleTypeDef EEPROM_SPI_PORT;
//Enable the EEPROM
//Accepts: SPI handle
//Returns: Success or failure of the enable operation
uint8_t Enable_EEPROM (SPI_TypeDef *spi_handle) {
uint16_t ewen = (0x04 << 8) | 0b00110000;
if (HAL_SPI_Transmit(spi_handle, &ewen, 1, HAL_MAX_DELAY) == HAL_OK) return TRUE;
else return FALSE;
}
//Disable the EEPROM
//Accepts: SPI handle
//Returns: Success or failure of the disable operation
uint8_t Disable_EEPROM (SPI_TypeDef *spi_handle) {
uint16_t ewds = (0x04 << 8) | 0b00000000;
if (HAL_SPI_Transmit(spi_handle, &ewds, 1, HAL_MAX_DELAY) == HAL_OK) return TRUE;
else return FALSE;
}
//Read from the EEPROM
//Accepts: SPI handle, memory address and data buffer where the read value will be stored
//Returns: Success or failure of read operation
uint8_t Read_EEPROM (SPI_TypeDef *spi_handle, uint8_t addr, uint16_t data) {
uint16_t write_package;
write_package = (READ << 8 | addr);
// if (HAL_SPI_Transmit(spi_handle, &write_package, 1, HAL_MAX_DELAY) == HAL_OK) {
// HAL_Delay(10);
// if (HAL_SPI_Receive(spi_handle, &data, 1, HAL_MAX_DELAY) == HAL_OK) return TRUE;
// else return FALSE;
// }
if (HAL_SPI_TransmitReceive(spi_handle, &write_package, &data, 1, HAL_MAX_DELAY) == HAL_OK) return TRUE;
else return FALSE;
}
//Write to the EEPROM
//Accepts: SPI handle, memory address and data to be written
//Returns: Success or failure of write operation
uint8_t Write_EEPROM (SPI_TypeDef *spi_handle, uint8_t addr, uint16_t data) {
uint16_t write_package[2];
write_package[0] = (WRITE << 8 | addr);
write_package[1] = data;
if (HAL_SPI_Transmit(spi_handle, write_package, 2, HAL_MAX_DELAY) == HAL_OK) return TRUE;
else return FALSE;
}
//Erase a specific memory address from the EEPROM
//Accepts: SPI handle and the memory address to be erased
//Returns: Success or failure of erase operation
uint8_t Erase_EEPROM (SPI_TypeDef *spi_handle, uint8_t addr) {
uint16_t write_package;
write_package = (ERASE << 8 | addr);
if (HAL_SPI_Transmit(spi_handle, &write_package, 1, HAL_MAX_DELAY) == HAL_OK) return TRUE;
else return FALSE;
}
EDIT: I’ve attached waveforms here as well.
Enable
Erase
Write
Without looking through your code in detail, I've spotted a possible problem: In order to complete an SPI operation, the chip select (CS) line usually needs to be pulled low before and set high again after every operation.
So, the EEPROM functions in your driver code probably need to first set the CS pin low, do some SPI operation, and set it high again after that.
For convenience, I usually add some simple helper functions to the driver source file:
static GPIO_TypeDef *_cs_port;
static uint16_t _cs_pin;
static void _chip_select(void)
{
HAL_GPIO_WritePin(_cs_port, _cs_pin, GPIO_PIN_RESET);
}
static void _chip_deselect(void)
{
HAL_GPIO_WritePin(_cs_port, _cs_pin, GPIO_PIN_SET);
}
In that case, I usually intialize the driver and and keep track of the peripheral instance and chip select GPIO, similar to this:
static SPI_HandleTypeDef *_spi;
static uint8_t _init = 0;
int8_t eeprom_init(
SPI_HandleTypeDef *spi,
GPIO_TypeDef *gpio_cs_port,
uint16_t gpio_cs_pin)
{
if (_init)
return -1;
_spi = spi;
_cs_port = gpio_cs_port;
_cs_pin = gpio_cs_pin;
/* do initialization here */
_chip_deselect();
_init = 1;
return 0;
}
int8_t eeprom_clear(void)
{
if (!_init)
return -1;
/* do de-initialization here */
_spi = 0;
_cs_port = 0;
_cs_pin = 0;
_init = 0;
return 0;
}
int8_t eeprom_op_x(void)
{
if (!_init)
return -1;
_chip_select();
op_x(); /* todo */
_chip_deselect();
return 0;
}
I hope this helps :) ! There might be other issues in your hardware/software; this is probably not the full solution to your problem.
BTW: There are also ways to use hardware chip select (STM32 SPI peripheral), which I've never used (SPI / NSS in the reference manual). As far as I can tell, you also used SPI_NSS_SOFT in your SPI configuration, which requires you to manually set the chip select line.
BTW: Unrelated, but maybe of interest: ST provides simple HAL functions to access external I2C flash (HAL_I2C_Mem_*() functions).
edit 0 (more findings by skimming through code / datasheet):
Read_EEPROM() will not work like this, the data read from the bus isn't accessible outside the function's scope (C issue). Instead, a pointer to a read buffer could be passed to the function (or the read data could be returned as return value). For example like this: uint8_t Read_EEPROM (SPI_TypeDef *spi_handle, uint8_t addr, uint8_t *data, uint8_t byte_count)
In Read_EEPROM(): HAL_SPI_TransmitReceive() won't read the incoming bytes, when used like this. It receives and transmits at the same time. So it would make sense to first write the read / address command, and then start reading the incoming bytes (like in your code that has been commented out).
In Enable_/Disable_/Read_/Erase_EEPROM(): The number of bytes (size) seems to be wrong, it should be 2 instead of 1, in order to make HAL_SPI_Transmit() / HAL_SPI_TransmitReceive() transmit/receive the right number of bytes.
This IC does not seem to be well suited to be used with normal
SPI, since it requires a very specific bit sequence which is
not byte aligned (like you said). It might make sense to bit bang
the communication (like you've mentioned), and pay attention to every
little bit stated in the datasheet...
Since this seems to be an early test, I'd try to keep it as simple as possible, and get a first enable/write/read operation going, by bit-twiddling the same SPI pins by hand (reconfigured as normal GPIOs), so that the problems with the STM32's byte oriented SPI HAL functions won't get in your way. And then work towards a nice little driver... Maybe the STM32's SPI can still be used in some way, it's hard to tell for me right now...

Kernel driver i2c Develop

On my board I have an I2C device that sets some register.
g_I2cDevFd = open("/dev/" UMAP_DEVNAME_I2C, O_RDWR, 0);
if (g_I2cDevFd < 0)
{
HI_FATAL_I2C("open I2C err.\n");
HI_I2C_UNLOCK();
return HI_ERR_I2C_OPEN_ERR;
}
How can I do that?
Best Regards
Your question is not clear much. But for I2C communication in Linux Os, Please refer this link Interfacing_with_I2C_Devices
Please use your device path in define UMAP_DEVNAME_I2C itself. ie, #define UMAP_DEVNAME_I2C "/dev/your_i2c_device"
Or use sprintf if you cant edit UMAP_DEVNAME_I2C ie,
char buff[100] = {0}; // size you can change according to your requirement
sprintf(buff,"/dev/%s",UMAP_DEVNAME_I2C);
g_I2cDevFd = open(buff, O_RDWR, 0);
/* Error check for open here*/
int addr = 0xFF; // 0xFF is Invalid, Give I2C address of your device
if (ioctl(g_I2cDevFd, I2C_SLAVE, addr) < 0) {
printf("Failed to acquire bus access and/or talk to slave.\n");
/* ERROR HANDLING; you can check errno to see what went wrong */
exit(1);
}
/* Write or Read*/