General usable MCP4728 quad DAC implementation only limited function has to be used together with the DevInterface lib
Dependents: mbedSerialInterface_talkback2 MCP4728test mbedSerialInterface_sequencer
Diff: mcp4728.cpp
- Revision:
- 0:7a0ebc527fb9
- Child:
- 1:cd7c70a46739
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mcp4728.cpp Fri Oct 23 19:35:27 2015 +0000 @@ -0,0 +1,119 @@ +#include "mcp4728.h" +#include "mbed.h" + + +#define VERSION_MCP4728_SRC "0.02" +// verions 0.02 has a fixed setDAC but now ch1 reacts on the heart beat some bit maniputation error in the setDac + +#define CMDFAST 0 +#define CMDWRITEDAC 2 // writes to the DAC and / or eeprom depending on the write funcion +//#define CMDWRITEI2CADDR 3 // handled in a different class +#define CMDWRITEVREF 4 +#define CMDWRITEGAIN 6 +#define CMDWRITEPWDDOWN 5 + +#define WRITEFCTMULTI 0 // write to multiple DAC ch given by ch selectio bits +#define WRITEFCTSEQ 2 // write to DAC AND eeprom, from ch given in ch selection bits to D +#define WRITEFCTSINGLE 3 // write to a singe DAC AND eeprom ch given in ch selection bits + +MCP4728::MCP4728(I2CInterface* i2cinterface, int device_address_bits ): _i2c_interface(i2cinterface) , + getVersion( VERSION_MCP4728_HDR,VERSION_MCP4728_SRC, __TIME__, __DATE__) +{ + + // Assemble the full I2C device address. + _device_address = 0xC0; // Prime the full device address with the device code. + _device_address |= (device_address_bits<<1); + // next has to be read back from the device but + + for ( int ch=0;ch<4;ch++) { + ChCfg[ch].pwr=Normal; + ChCfg[ch].vref=InternRef; + ChCfg[ch].gain=GainX2; + } +} + +int MCP4728::getDACvalue(int& value, int ch){ + // has to limit to reading only the dac value not the other items. + enum PowerMode mode; enum PowerMode mode_eeprom; int dac_value; int dac_value_eeprom; bool eeprom_write_in_progress; + int status = read( mode, mode_eeprom, dac_value, dac_value_eeprom, eeprom_write_in_progress); + value=dac_value; + return status; +} + +int MCP4728::read(enum PowerMode& mode, enum PowerMode& mode_eeprom, int& dac_value, int& dac_value_eeprom, bool& eeprom_write_in_progress) +{ + char data[5]; + int result; + + // Read the raw data from the device. + result = _i2c_interface->read(_device_address, data, sizeof(data)/sizeof(*data), false); + + // Parse the raw data, extracting our fields. Refer to MCP4728 ref manual, section 6.2 + if (result == 0) + { + eeprom_write_in_progress = (data[0] & 0x80)? false:true; + + mode = (enum PowerMode) ((data[0] & 0x06)>>1); + + dac_value = (data[1]<<4) + (data[2]>>4); + + mode_eeprom = (enum PowerMode)((data[3] & 0x60)>>5); + + dac_value_eeprom = ((data[3] & 0x0F) <<8) + data[4]; + } + + return result; +} + + +int MCP4728::setDACvalue( int value, int ch){ + char data[3], tmp ; + /* data[0] = CMDWRITEDAC << 6; // select write DAC function + data[0] = data[0] | WRITEFCTMULTI << 4 ; // select write multi ch no eeprom + ch =ch & 3; + tmp =(char) ch; // select the channel + data[0] = data[0] | tmp ; + data[0] = data[0] | 0 ; // update now , assuming !LDAC =0 +*/ + data[2] = 0xFF & (char)value; +/* value=value >>8; + data[1] = 0x0F & (char)value; + data[1] = data[1] | (char)( ChCfg[ch].gain <<4); //set gain + data[1] = data[1] | (char)( ChCfg[ch].pwr <<5); // set pwr mode + data[1] = data[1] | (char)( ChCfg[ch].vref <<7); // set pwr mode +*/ + data[0]= 0x52; // 0b0101 0010 ch 1 !UDAC=0 + data[1]= 0x17; // 0b0000 0111 ref=Vdd, pwd =0 normal ; gain =1 d11=0 ,111, + return _i2c_interface->write(_device_address, data, sizeof(data)/sizeof(*data), false); + + +} + + + + +int MCP4728::write(enum PowerMode mode, int dac_value, bool writeToEeprom) +{ + char data[3]={0}; + int write_command; + + //Which write command are we to use? + if (writeToEeprom == true) + { + //Write DAC Register and EEPROM + write_command = 3; + } + else + { + //Write DAC Register + write_command = 2; + } + + //Assemble our three bytes of data - Refer to MCP4728 ref manual, section 6. + data[0] = (write_command <<5) | ((int)mode<<1); + data[1] = (dac_value>>4); + data[2] = (dac_value<<4); + + // Now write them to the device. + return _i2c_interface->write(_device_address, data, sizeof(data)/sizeof(*data), false); +} \ No newline at end of file