Hardware
Hardware Requierments
- Any 96Boards CE Board
- Shiratech FPGA Mezzanine
- I2C Shield or Sensor
- For the Purpose of this guide I will be using:
HArdware Setup
- Connect the Shiratech Mezzanine to the 96Boards CE Development Board
- Connect the Relay shield on the FPGA Mezzanine’s Arduino Header
Software setup
- Install MRAA on 96Boards CE
- Download FPGA Mezzanine Library
- Paste the following code into a file named relay.c ```C /* // Title: relay.c // Author: Sahaj Sarup // Copyright (c) 2019 Linaro Limited */
#include
/* mraa header */ #include “mraa/i2c.h” #include “fpga_mezz.h”
int main() { /Initialise MRAA I2C/ mraa_result_t status = MRAA_SUCCESS; mraa_i2c_context i2c; mraa_init();
i2c = mraa_i2c_init(I2C_BUS);
/*Use I2C Bus0 for FPGA Mezzzanine*/
int input, ver;
if (i2c == NULL) {
fprintf(stderr, "Failed to initialize I2C\n");
mraa_deinit();
return EXIT_FAILURE;
}
/* set slave address */
status = mraa_i2c_address(i2c, FPGA_MEZZI_ADDR);
if (status != MRAA_SUCCESS) {
}
/* Simple test function to test the I2C Communication */
if(test(i2c)==0)
{
printf("test Passed\n");
}
else
{
printf("test Failed\n");
return 1;
}
/* Check Firmware Revision of the FPGA Mezzanine */
ver = check_version(i2c);
if(ver == -1)
{
printf("Version Check Error\n");
return 1;
}
else
{
printf("Version %d\n",&ver);
}
/* Set Pins 7,6,5 and 4 as output */
pinMode(7,OUTPUT,i2c);
pinMode(6,OUTPUT,i2c);
pinMode(5,OUTPUT,i2c);
pinMode(4,OUTPUT,i2c);
while(1)
{
/* Sequentially toggle each relay on and off. */
digitalWrite(7,LOW,i2c);
sleep(1);
digitalWrite(7,HIGH,i2c);
sleep(1);
digitalWrite(6,LOW,i2c);
sleep(1);
digitalWrite(6,HIGH,i2c);
sleep(1);
digitalWrite(5,LOW,i2c);
sleep(1);
digitalWrite(5,HIGH,i2c);
sleep(1);
digitalWrite(4,LOW,i2c);
sleep(1);
digitalWrite(4,HIGH,i2c);
sleep(1);
} }
```
- Compile using:
gcc relay.c <path-to-fpga_mezz_lib>/src/fpga_mezz.c -o relay -I<path-to-fpga_mezz_lib>/include/ - Run using:
sudo ./relay- All four relays should turn on and off, one at a time.