I am working on a university project in which i need to interface pic18f4550 with i2c EEPROM.
I read many codes and saw many projects on this topic. and I wrote a sample code from MPLAB C18 ( and i tried many codes also) but no one worked with me.
I dont where is the problem. Every thing is ok with my code and with my circuit, but the sck did not genrate clk for writing and nothing has been wriiten to eeprom. so if any one can help me plz.
NOTE: I can't post an image of my circuit, since I'm new user !
Here is the code:
#include "p18f4550.h"
#include "i2c.h"
#pragma config FOSC = HS
#pragma config PWRT = OFF
#pragma config BOR = OFF
#pragma config MCLRE = ON
#pragma config PBADEN = OFF
#pragma config ICPRT = OFF
#pragma config LVP = OFF
#pragma config WDT = OFF,DEBUG=OFF
unsigned char arraywr[] = {1,2,3,4,5,6,7,8,0};
unsigned char arrayrd[20];
//***************************************************
void main(void)
{
OpenI2C(MASTER, SLEW_ON);// Initialize I2C module
SSPADD = 10; //400kHz Baud clock(10) #20MHz
while(1)
{
EEByteWrite(0xA0, 0x30, 0xA5);
EEAckPolling(0xA0);
EECurrentAddRead(0xA0);
EEPageWrite(0xA0, 0x70, arraywr);
EEAckPolling(0xA0);
EESequentialRead(0xA0, 0x70, arrayrd, 20);
EERandomRead(0xA0,0x30);
}
}
Thanks in advance
It doesnt look like you have set up the port pins for digital input and output. Check the datasheet for which pins are used for I2C and set the appropriate TRIS bits. You should also check that the analogue functions for the same pins is disabled (ANSEL register). Enabling the I2C module is not enough on its own.
Related
I am using a ESP32-SIM800L with GPRS / MS5803-14BA / BME280 / SH1106 OLED
The modem and sensor setup (using TwoWire ) is as follows (relevant extracts only):
#include <Wire.h>
...
#define I2C_SDA 21
#define I2C_SCL 22
#define I2C_SDA_2 18
#define I2C_SCL_2 19
...
#include <SparkFun_MS5803_I2C.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BME280.h>
#include "SH1106Wire.h"
TwoWire I2CPower = TwoWire(0);
TwoWire I2CMS = TwoWire(1); // I2C bus for MS5803 # 0x77
TwoWire I2CBME = TwoWire(1); // I2C bus for BME280 # 0x76
TwoWire I2CSH = TwoWire(1); // I2C bus for SH1106 OLED # 0x3c
MS5803 sensor(ADDRESS_LOW); // default is ADDRESS_HIGH = 0x76 // ADDRESS_LOW = 0x77
Adafruit_BME280 bme;
SH1106Wire display(0x3c, I2C_SDA_2, I2C_SCL_2);
...
void setup() {
...
I2CPower.begin(I2C_SDA, I2C_SCL, 400000); // start I2C bus No. 1 for SIM800L
I2CMS.begin(I2C_SDA_2, I2C_SCL_2, 400000); // start I2C bus No. 2 for MS5803
I2CBME.begin(I2C_SDA_2, I2C_SCL_2, 400000); // start I2C bus No. 2 for BME280
I2CSH.begin(I2C_SDA_2, I2C_SCL_2, 400000); // start I2C bus No. 2 for SH1106 OLED
...
// Init BME280 # 0x76
if (!bme.begin(0x76, &I2CBME)) {
Serial.println("No valid BME280 sensor # 0x76, check wiring!");
} else {
Serial.println("BME280 # 0x76 : Ok");
}
// Init MS5803 # 0x77
sensor.reset();
delay(500);
//sensor.begin();
//delay(500);
if (!sensor.begin()) {
Serial.println("No valid MS5803 sensor # 0x77");
} else {
Serial.println("MS5803 # 0x77 : Ok");
}
// Init SH1106 OLED # 0x3c
display.init();
Serial.println("SH1106 OLED # 0x3c : SCREEN CHECK");
display.flipScreenVertically();
display.setFont(ArialMT_Plain_16);
display.setTextAlignment(TEXT_ALIGN_LEFT);
display.drawString(0,0,"SCREEN ON");
display.display();
...
} // End void setup()
void loop() {
read sensors and report & etc. ...
}
The Modem, BME280 and SH1106 OLED are all found and work, however the MS5803 is not picked up.
There are no I2C address clashes (0x76,0x33,0x77 respectivly).
Object creation or initialization of the BME280 and SH1106 OL allow explicit SDA/SCL pin assignments:
SH1106Wire display(0x3c, I2C_SDA_2, I2C_SCL_2);
...
bme.begin(0x76, &I2CBME)
however creation of the MS5803 object and its initialization has no provision for this:
MS5803 sensor(ADDRESS_LOW);
...
sensor.begin();
Trying to enter explicit pin numbers or reference to its TwoWire object in these expressions produces an error warning that there is no such function to allow such assignment.
Basically, if the modem, the BME280 and SH1106 OLED are not used, and TwoWire is not needed or invoked, then the MS5803 runs perfectly without pin assignment using the default I2C Pins (which for my ESP32Sim800L are 21/22). It is the issue of trying to put the sensor on a second I2C wire that seems problematic.
Can anyone explain how to use the MS5803 with TwoWire? Having looked on GitHub at the Sparkfun .h & .cpp I cant see one or how to explicitly set the SDA/SCL pins. Is there a way. Any pointers much appreciated.
I'm working on a project using an stm32f030rc. I need to use PC15 as a GPIO input but it appears I'm unable to.
I understand the couple PC14/PC15 is shared with the LFE oscillator, but of course I'm not using that function. Moreover, I am able to read the correct pin level on the PC14 GPIO. In the datasheed regarding my model the PC15 pin is marked as a I/O with OSC32_OUT as additional function: can it be used as input at all?
For reference, this is the C code I'm using to test the functionality; I'm using libopencm3 for initialization.
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/gpio.h>
static void clock_setup(void)
{
rcc_clock_setup_in_hsi_out_48mhz();
/* Enable GPIOA, GPIOB, GPIOC clock. */
rcc_periph_clock_enable(RCC_GPIOA);
rcc_periph_clock_enable(RCC_GPIOB);
rcc_periph_clock_enable(RCC_GPIOC);
rcc_periph_clock_enable(RCC_DBGMCU);
/* Enable clocks for GPIO port B and C*/
gpio_mode_setup(GPIOA, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO5);
gpio_mode_setup(GPIOC, GPIO_MODE_INPUT, GPIO_PUPD_NONE, GPIO15);
gpio_mode_setup(GPIOC, GPIO_MODE_INPUT, GPIO_PUPD_NONE, GPIO14);
}
int main(void)
{
unsigned long long i = 0;
clock_setup();
/* Blink the LED (PA8) on the board with every transmitted byte. */
while (1)
{
gpio_toggle(GPIOA, GPIO5); /* LED on/off */
for (i = 0; i < 400000; i++) /* Wait a bit. */
__asm__("nop");
// This conditional is never entered
if (gpio_get(GPIOC, GPIO15) == 0) {
__asm__("nop");
__asm__("nop");
__asm__("nop");
}
// This one works
if (gpio_get(GPIOC, GPIO14) == 0) {
__asm__("nop");
__asm__("nop");
__asm__("nop");
}
}
return 0;
}
PC14 & PC15 have the same configuration properties. Of course, there are some limitations regarding using these pins as outputs (including PC13), but it should be okay to use them as inputs as long as you don't activate LSE functionality.
PC14 & PC15 are GPIO inputs after power-up and considering that LSE is disabled by default, you should be able to use them directly even without any configuration.
As you don't have any problems with PC14, I suspect 3 possible causes:
1) A bug in the GPIO code the library provides. Although it's very unlikely, it's easy to test. You can remove the configuration code for PC14 & PC15, as they are GPIO inputs after power-up by default. This eliminates the possibility of having a bug in gpio_mode_setup() function. To avoid using gpio_get() function, you can use the following code:
if (GPIOC->IDR & (1 << 15) == 0)
2) A bug in the clock config code the library provides. Again, this one is very unlikely, but you can test it by removing the rcc_clock_setup_in_hsi_out_48mhz() function. MCU uses HSI running at 8 MHz after power-up.
3) This can be a hardware problem. I suggest checking the voltage on PC15. Test it by physically connecting it to GND. Also measure PC14 for comparison. Among these 3 possible causes I can think of, this is the most probable one.
I am using STM32F103C8T6 board and CubeMX to generate the code. I need to receive the GPS data from Quectel L89 module from UART2 port. when I try that I get some junk values only... I am using HAL_UART_Receive to receive data and print it in the putty console. Any help would be greatly appreciated.
This is my code.
void task1(void)
{
char *buffer = NULL;
buffer = (char*)malloc(400 * sizeof(char));
while(1)
{
HAL_UART_Receive(&huart2,buffer,350,500);
int size = strlen(buffer);
HAL_UART_Transmit(&huart1,buffer,size,500);
HAL_Delay(1000);
}
}
Image of the Result
try this
HAL_UART_Receive(&huart2,(uint8_t *)buffer,350,500);
and
HAL_UART_Transmit(&huart1,(uint8_t *)buffer,size,500);
Because arguments needed for HAL functions are of uint8_t * type.
I am having trouble with my university project for embedded systems. The goal is to establish an interface between a SM5100B GSM module and ATMEGA16A microcontroller, using UART (which I did, using the correct ports from the datasheets), and to be able to send/receive simple SMS messages by sending AT commands trough the Tx and Rx ports from atmega to gsm and vice versa, via C code in Atmel.(not using hyperterminal)
When I tested the GSM module using TeraTerm, i was able to connect properly, and send AT commands easily, also managed to send and recieve an SMS with the SIM card inserted, so everything works fine.
Now I'm trying to do that using the microcontroller.
Here is the code I have so far:
#define F_CPU 7372800UL
#include <stdio.h>
#include <stdlib.h>
#include <util/delay.h>
#include <avr/io.h>
#include <string.h>
#define BAUD 9600
#define MYUBRR ((F_CPU/16/BAUD)-1) //BAUD PRESCALAR (for Asynch. mode)
void GSM_init(unsigned int ubrr ) {
/* Set baud rate */
UBRRH = (unsigned char)(ubrr>>8);
UBRRL = (unsigned char)ubrr;
/* Enable receiver and transmitter */
UCSRB = (1<<RXEN)|(1<<TXEN);
/* Set frame format: 8data, 2stop bit */
UCSRC = (1<<URSEL)|(1<<USBS)|(3<<UCSZ0);
}
void USART_Transmit(char data ) {
/* Wait for empty transmit buffer */
while ( !( UCSRA & (1<<UDRE)) );
/* Put data into buffer, sends the data */
UDR = data;
}
void USART_Transmits(char data[] ) {
int i;
for(i=0; i<strlen(data); i++) {
USART_Transmit(data[i]);
_delay_ms(300);
}
}
int main(void)
{
GSM_init(MYUBRR);
char text_mode[] = "AT+CMGF=1";
char send_sms[] = "AT+CMGS=";
char phone_number[] = "00385*********";
char sms[] = "gsm sadness";
USART_Transmits(text_mode);
_delay_ms(1000);
USART_Transmits(send_sms);
_delay_ms(1000);
USART_Transmit(34);//quotation mark "
//_delay_ms(300);
USART_Transmits(phone_number);
//_delay_ms(300);
USART_Transmit(34);//quotation mark "
//_delay_ms(300);
USART_Transmit(13);//enter
//_delay_ms(300);
USART_Transmits(sms);
_delay_ms(1000);
USART_Transmit(26);//ctrl+z
_delay_ms(300);
USART_Transmit(13);//enter
_delay_ms(3000);
while (1)
{
}
}
However, my code isn't working, it's not sending the message.
The functions for transmitting are taken from the datasheet and everywhere on the internet I search I find the same ones over and over again.
Is the problem in AT responses that I'm not reading correctly? Or in parsing AT commands to the serial port?
Can anybody help me understand where I'm going wrong with this, or where I can look for to understand how to make this work?
I am new to modbus. I have spent hours reading the Help(?) files, which never seem to give you an example! I am using C on a Raspberry Pi, model3 and have installed libmodbus. I am trying to talk to an epSolar solar panel controller via an FTDI USB to RS485 converter.
The epSolar docs say that the Read Input registers start at address 3000 and continue to 311D. I am trying to read 3104.
I modified the code below. It connects to the device but trying to read input register 0x04 always returns -1:
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <modbus.h>
enum {TCP, RTU};
int main(int argc, char *argv[])
{
int socket;
modbus_t *ctx;
modbus_mapping_t *mb_mapping;
int rc;
int use_backend;
int i;
uint16_t tab_reg[64];
use_backend = RTU;
printf("Waiting for Serial connection\n");
ctx = modbus_new_rtu("/dev/SOLAR", 115200, 'N', 8, 1);
modbus_set_slave(ctx, 0);
//modbus_connect(ctx);
if(modbus_connect(ctx) == -1)
{
fprintf(stderr, "Serial connection failed:
%s\n", modbus_strerror(errno));
modbus_free(ctx);
return -1;
}
printf("Serial connection started!\n");
mb_mapping = modbus_mapping_new(MODBUS_MAX_READ_BITS, 0,
MODBUS_MAX_READ_REGISTERS, 0);
if(mb_mapping == NULL)
{
fprintf(stderr, "Failed to allocate the mapping: %s\n",
modbus_strerror(errno));
modbus_free(ctx);
return -1;
}
rc = modbus_read_input_registers(ctx, 1, 0x0A, tab_reg);
if(rc == -1)
{
fprintf(stderr, "%s\n", modbus_strerror(errno));
return -1;
}
for(i=0; i < rc; i++)
printf("reg[%d]=%d (0x%X)\n", i, tab_reg[i], tab_reg[i]);
modbus_mapping_free(mb_mapping);
modbus_free(ctx);
modbus_close(ctx);
return 0;
}
It connects fine and allocates the mapping, but rc is always -1 with error message that the port has timed out.
I have run out of ideas and feel like I am navigating through treacle!
Any help most appreciated.
I am also new to Modbus. With my current experience, make sure you are allocating enough memory for the tab_reg for storing the results. Also try setting the Debug mode on i.e modbus_set_debug(ctx, TRUE); to Check for the request and response code.
I know this is a really old question, but hopefully this answer will help anyone who lands here via a Google search.
I can see a few points that need some help.
As commented by Saad above, the modbus server ID above is incorrect. ID 0 is reserved for broadcast messages, which a slave will not respond to. Find out what the Modbus ID for the target device is, and use that.
I think what's tricking you is that you'll also always get a proper "connect" as long as the serial port you provided is valid. This isn't a connection to any particular device so much as it's a connection to the Modbus network port. You're getting a timeout because a response was expected by libmodbus, but no response was received on the wire.
There are several other little troubles in the code presented, but given the age of this post I almost feel like I'm nitpicking something the OP probably already solved. The big problem is the unworkable slave ID. Other minor problems include: unnecessary use of modbus_mapping (struct for use on server/slaves), possible misallocation of modbus_mapping (no space allocated for input registers).