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@1:6557cf755742, 2016-01-24 (annotated)

Committer:
sk398
Date:
Sun Jan 24 15:10:48 2016 +0000
Revision:
1:6557cf755742
Parent:
0:870a29ad1074
Child:
2:b6789ad2af2b
Child:
4:5ccaaacec14f
StandardMode method added

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sk398 0:870a29ad1074 1 #include "mbed.h"
sk398 0:870a29ad1074 2 #include "SD20.h"
sk398 0:870a29ad1074 3
sk398 1:6557cf755742 4 SD20::SD20(I2C *bus)
sk398 0:870a29ad1074 5 {
sk398 0:870a29ad1074 6 _bus = bus;
sk398 1:6557cf755742 7 _bus -> frequency(BUS_FREQ);
sk398 0:870a29ad1074 8 }
sk398 0:870a29ad1074 9
sk398 1:6557cf755742 10 int SD20::UpdateChannel(char *newDutyCycle)
sk398 0:870a29ad1074 11 {
sk398 1:6557cf755742 12 // Output new duty cycle to SD20, return 0 if successful, 1 if unsuccessful
sk398 1:6557cf755742 13 if(_bus -> write(SD20_ADDRESS,newDutyCycle,OUT_BUF_LEN))
sk398 0:870a29ad1074 14 {
sk398 0:870a29ad1074 15 printf("I2C Failed to write\r\n");
sk398 0:870a29ad1074 16 return 1;
sk398 0:870a29ad1074 17 }
sk398 0:870a29ad1074 18 else
sk398 0:870a29ad1074 19 {
sk398 1:6557cf755742 20 printf("0x%02x sent to Reg: 0x%02x\r\n",*(newDutyCycle+1),*newDutyCycle);
sk398 0:870a29ad1074 21 return 0;
sk398 0:870a29ad1074 22 }
sk398 0:870a29ad1074 23 }
sk398 0:870a29ad1074 24
sk398 1:6557cf755742 25 int SD20::StartStopChannel(uint8_t ServoChannel,bool Start)
sk398 0:870a29ad1074 26 {
sk398 1:6557cf755742 27 // Startup a new channel, return 0 if successful, 1 if unsuccessful
sk398 0:870a29ad1074 28 if(Start == CHANNEL_START)
sk398 0:870a29ad1074 29 {
sk398 1:6557cf755742 30 char newDutyCycle[] = {ServoChannel,CHANNEL_START};
sk398 1:6557cf755742 31 if(_bus -> write(SD20_ADDRESS,newDutyCycle,OUT_BUF_LEN))
sk398 0:870a29ad1074 32 {
sk398 0:870a29ad1074 33 printf("I2C Failed to write\r\n");
sk398 0:870a29ad1074 34 return 1;
sk398 0:870a29ad1074 35 }
sk398 0:870a29ad1074 36 else
sk398 0:870a29ad1074 37 {
sk398 1:6557cf755742 38 printf("0x%02x sent to Reg: 0x%02x\r\n",*(newDutyCycle+1),*newDutyCycle);
sk398 0:870a29ad1074 39 return 0;
sk398 0:870a29ad1074 40 }
sk398 0:870a29ad1074 41 }
sk398 1:6557cf755742 42
sk398 1:6557cf755742 43 // Stop channel, return 0 if successful, 1 if unsuccessful
sk398 0:870a29ad1074 44 else
sk398 0:870a29ad1074 45 {
sk398 1:6557cf755742 46 char newDutyCycle[] = {ServoChannel,CHANNEL_STOP};
sk398 1:6557cf755742 47 if(_bus -> write(SD20_ADDRESS,newDutyCycle,OUT_BUF_LEN))
sk398 0:870a29ad1074 48 {
sk398 0:870a29ad1074 49 printf("I2C Failed to write\r\n");
sk398 0:870a29ad1074 50 return 1;
sk398 0:870a29ad1074 51 }
sk398 0:870a29ad1074 52 else
sk398 0:870a29ad1074 53 {
sk398 1:6557cf755742 54 printf("0x%02x sent to Reg: 0x%02x\r\n",*(newDutyCycle+1),*newDutyCycle);
sk398 0:870a29ad1074 55 return 0;
sk398 0:870a29ad1074 56 }
sk398 0:870a29ad1074 57 }
sk398 0:870a29ad1074 58 }
sk398 0:870a29ad1074 59
sk398 1:6557cf755742 60 int SD20::SetStandardMode()
sk398 1:6557cf755742 61 {
sk398 1:6557cf755742 62 char outputBuf[] = {STD_ETD_MODE_CTRL,STD_MODE};
sk398 1:6557cf755742 63 if(_bus -> write(SD20_ADDRESS,outputBuf,OUT_BUF_LEN))
sk398 1:6557cf755742 64 {
sk398 1:6557cf755742 65 printf("I2C Failed to write\r\n");
sk398 1:6557cf755742 66 return 1;
sk398 1:6557cf755742 67 }
sk398 1:6557cf755742 68 else
sk398 1:6557cf755742 69 {
sk398 1:6557cf755742 70 printf("0x%02x sent to Reg: 0x%02x\r\n",*(outputBuf+1),*outputBuf);
sk398 1:6557cf755742 71 return 0;
sk398 1:6557cf755742 72 }
sk398 1:6557cf755742 73 }
sk398 1:6557cf755742 74