Steven Kay / SD20

This is a driver to control the SD20 20 Channel I2C to Servo Driver Chip from www.robot-electronics.co.uk (http://www.robot-electronics.co.uk/htm/sd20tech.htm). This driver will allow a servo channel to be started up, stopped and the duty cycle altered in standard mode. No attempt to include the extended mode is included.

SD20.cpp

Committer:
sk398
Date:
2016-02-25
Revision:
4:5ccaaacec14f
Parent:
1:6557cf755742

File content as of revision 4:5ccaaacec14f:

#include "mbed.h"
#include "SD20.h"
      
SD20::SD20(I2C *bus)
{
    _bus = bus;
    _bus -> frequency(BUS_FREQ);
}

int SD20::UpdateChannel(char *newDutyCycle)
{
        // Output new duty cycle to SD20, return 0 if successful, 1 if unsuccessful
        if(_bus -> write(SD20_ADDRESS,newDutyCycle,OUT_BUF_LEN))
        {
            printf("I2C Failed to write\r\n");
            return 1;
        }
        else
        {
            printf("Reg: 0x%02x Data: 0x%02x\r\n",*newDutyCycle,*(newDutyCycle+1));
            return 0;
        }
}

int SD20::StartStopChannel(uint8_t ServoChannel,bool Start)
{
        // Startup a new channel, return 0 if successful, 1 if unsuccessful
        if(Start == CHANNEL_START)
        {
            char newDutyCycle[] = {ServoChannel,CHANNEL_START};
            if(_bus -> write(SD20_ADDRESS,newDutyCycle,OUT_BUF_LEN))
            {
                printf("I2C Failed to write\r\n");
                return 1;
            }
            else
            {
                printf("Reg: 0x%02x Data: 0x%02x\r\n",*newDutyCycle,*(newDutyCycle+1));
                return 0;
            }
        }
        
        // Stop channel, return 0 if successful, 1 if unsuccessful
        else
        {
           char newDutyCycle[] = {ServoChannel,CHANNEL_STOP};
            if(_bus -> write(SD20_ADDRESS,newDutyCycle,OUT_BUF_LEN))
            {
                printf("I2C Failed to write\r\n");
                return 1;
            }
            else
            {
                printf("Reg: 0x%02x Data: 0x%02x\r\n",*newDutyCycle,*(newDutyCycle+1));
                return 0;
            }
        }
}

int SD20::SetStandardMode()
{
        char outputBuf[] = {STD_ETD_MODE_CTRL,STD_MODE};
        if(_bus -> write(SD20_ADDRESS,outputBuf,OUT_BUF_LEN))
        {
            printf("I2C Failed to write\r\n");
            return 1;
        }
        else
        {
            printf("0x%02x sent to Reg: 0x%02x\r\n",*(outputBuf+1),*outputBuf);
            return 0;
        }    
}