First Last
Library to work with the LDC1000 from Texas Instruments
LDC1000
This library was written to interface to Texas Instruments' LDC1000 in order to perform inductance measurement. This libary needs a SPI peripheral on your mbed device to talk to the LDC1000.
Clock
The LDC1000 needs a high speed clock for its internal frequency counter. In order to provide this clock, the FastPWM library is used. This may change the behaviour of other PWM channels, please be aware of that, and read the FastPWM documentation to understand the implications.
Unsupported
Not supported (yet):
- Setting the RpMAX and RpMIN values
- Setting the interrupt pin functionality
Diff: LDC1000.cpp
- Revision:
- 8:b5fb9681869c
- Parent:
- 7:7f1522ad3df5
- Child:
- 9:6e2d808b113d
--- a/LDC1000.cpp Tue May 26 14:50:16 2015 +0000
+++ b/LDC1000.cpp Fri May 29 09:28:46 2015 +0000
@@ -20,27 +20,28 @@
wait_us(100);
mode(LDC_MODE_STANDBY);
setFrequency(f_external);
- wait(0.1);
- //setOutputPower(LDC_AMPLITUDE_4V);
+ wait(0.1);
wait_us(10);
- //setResponseTime(LDC_RESPONSE_384);
- //setWatchdog(5000);
+
+ setWatchdog(5000);
+ setResponseTime(LDC_RESPONSE_6144);
+ setOutputPower(LDC_AMPLITUDE_4V);
-// Write comando's like in EVM start log:
- //writeSPIregister(0x0B,0x00);
- //writeSPIregister(0x01,0x0E);
- //writeSPIregister(0x02,0x3C);
+//*** Write comando's like in EVM start log:
+/* writeSPIregister(0x0B,0x00); */
+ writeSPIregister(0x01,0x0E);
+ writeSPIregister(0x02,0x3C);
writeSPIregister(0x03,0x15);
- writeSPIregister(0x04,0x17);
- writeSPIregister(0x05,0x00);
- //writeSPIregister(0x06,0x50);
- //writeSPIregister(0x07,0x14);
- //writeSPIregister(0x08,0xC0);
- //writeSPIregister(0x09,0x12);
- //writeSPIregister(0x0A,0x04);
-// writeSPIregister(0x0C,0x01);
- //writeSPIregister(0x0B,0x01);
-
+ writeSPIregister(0x04,0x17);
+ writeSPIregister(0x05,0x00);
+ writeSPIregister(0x06,0x50);
+ writeSPIregister(0x07,0x14);
+ writeSPIregister(0x08,0xC0);
+ writeSPIregister(0x09,0x12);
+ writeSPIregister(0x0A,0x04);
+ writeSPIregister(0x0C,0x01);
+ writeSPIregister(0x0B,0x01);/*
+*/
mode(LDC_MODE_ACTIVE);
}
@@ -50,7 +51,7 @@
_amplitude = amplitude;
readSPI(&buffer, 0x04);
buffer &= 0xE7; //clear amplitude bits
- buffer |= (amplitude<<3) & 0xE7;
+ buffer |= (amplitude<<3) & 0x18;
writeSPI(&buffer,0x04);
}
@@ -60,7 +61,6 @@
uint8_t buffer;
buffer = 68.94*log(frequency/2500);
writeSPI(&buffer,0x03);
-
}
void LDC1000::setResponseTime(LDC_RESPONSE responsetime)
@@ -70,6 +70,7 @@
readSPI(&buffer, 0x04);
buffer &= 0xF8; //clear responsetime bits
buffer |= responsetime & 0x07;
+ //writeSPIregister(0x04,buffer);
writeSPI(&buffer,0x04);
}
@@ -82,12 +83,33 @@
float LDC1000::getInductance()
{
- uint16_t resp[] = {192, 384, 768, 1536, 3072, 6144};
+ uint16_t resp[] = {0,0,192, 384, 768, 1536, 3072, 6144};
_raw_l = readRawCounts();
_fsensor = (_frequency/(_raw_l*3.0))*resp[(uint8_t)(_responsetime)];
return 1./(cap*pow(2*PI*_fsensor,2));
};
+
+/* oude code terugzetten*/
+
+uint32_t LDC1000::readRawCounts(void)
+{
+ //union
+ //{
+ // uint8_t buf[4];
+ // uint32_t value;
+ //} val;
+ //val.value = 0;
+ uint8_t val[5];
+ readSPI(val,0x21,5);
+ return (uint32_t)(*(&val[2]));
+}
+
+
+
+
+
+ /*
uint32_t LDC1000::readRawCounts(void)
{
union
@@ -95,13 +117,11 @@
uint8_t buf[4];
uint32_t value;
} val;
- val.value = 0;
- uint8_t bla[5];
- readSPI(bla,0x21,5);
+ val.value = 8;
+ readSPI(val.buf,0x23,3);
return val.value;
}
-
-
+*/
void LDC1000::readSPI(uint8_t *data, uint8_t address, uint8_t num_bytes)
{
@@ -123,4 +143,20 @@
_spiport.write(data[i]);
}
_cs_pin.write(1);
-}
\ No newline at end of file
+}
+
+// EXTRA test get and print variables values to verify (to calculate the induction)
+// Begin ***********************************************************
+ float LDC1000::get_raw_l() {_raw_l = readRawCounts();
+ return _raw_l;};
+ float LDC1000::get_fsensor() {
+ uint16_t resp[] = {0, 0, 192, 384, 768, 1536, 3072, 6144};
+ _raw_l = readRawCounts();
+ _fsensor = (_frequency/(_raw_l*3.0))*resp[(uint8_t)(_responsetime)];
+ return _fsensor;};
+
+ float LDC1000::get_frequency() {return _frequency;};
+ float LDC1000::get_responsetime() {return _responsetime;};
+ float LDC1000::get_cap() {return cap;};
+// END ***********************************************************
+
LDC1000