Kian Sek Tee
8 channels ADC ic communicating via SPI.
Revision 0:c4617b633a1e, committed 2010-02-26
- Comitter:
- teekiansek
- Date:
- Fri Feb 26 18:16:20 2010 +0000
- Commit message:
Changed in this revision
| main.cpp | Show annotated file Show diff for this revision Revisions of this file |
| mbed.bld | Show annotated file Show diff for this revision Revisions of this file |
diff -r 000000000000 -r c4617b633a1e main.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Fri Feb 26 18:16:20 2010 +0000
@@ -0,0 +1,132 @@
+#include "mbed.h"
+#include "TextLCD.h"
+
+SPI _spi(p5,p6,p7); //mosi, miso, sck
+DigitalOut cs(p8); // chip select of MCP3008
+TextLCD lcd(p24, p25, p26, p27, p28, p29, p30); // rs, rw, e, d0, d1, d2, d3
+
+
+int main() {
+ int _data1;
+ int _data2;
+ cs=1; // deselect everything
+ wait(0.001);
+ _spi.format(8,0); //see page1 of MCP3008 manual
+ _spi.frequency(1000000); //see page4 of MCP3008 manual
+
+//******************************************************************
+// MCP3008 clock sequence and control bits
+//Once cs low, send start bit ==> 0x01 Not expecting any return
+//next, send control bits Expecting return B9, B8
+//next, send anything, say 0x00, expecting return B7-B0
+//next shift B9,B8 left 8bits
+//next merge B9,B8 and B7-B0 to form 16bits data
+//next, mask off bit15-bit10, to get a clean 10 bit data
+//*******************************************************************
+
+//*******************************************************************
+// 1st 8bits 2nd 8bits 3rd 8bits
+//ch0 0x01 0x80 0x00
+//ch1 0x01 0x90 0x00
+//ch2 0x01 0xA0 0x00
+//ch3 0x01 0xB0 0x00
+//ch4 0x01 0xC0 0x00
+//ch5 0x01 0xD0 0x00
+//ch6 0x01 0xE0 0x00
+//ch7 0x01 0xF0 0x00
+//*******************************************************************
+
+
+
+ while (1) {
+
+//ch0.
+ cs=0; //cs low. start data collection
+ _spi.write(0x01); //write start bit. Not expecting return
+ _data1=_spi.write(0x80); //write control bit, expecting return B9, B8
+ _data2=_spi.write(0x00); //write anything, expecting return B7-B0
+ int ch0 =(_data1<<8) | _data2; //merge two 8bits data becoming 16bits data
+ ch0 = ch0 & 0x03FF; // mask off bit15 - bit10
+ cs=1; //cs high. end of data collection
+
+//ch1
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0x90);
+ _data2=_spi.write(0x00);
+ int ch1 =(_data1<<8) | _data2;
+ ch1 = ch1 & 0x03FF;
+ cs=1;
+
+
+//ch2
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0xA0);
+ _data2=_spi.write(0x00);
+ int ch2 =(_data1<<8) | _data2;
+ ch2 = ch2 & 0x03FF;
+ cs=1;
+
+
+//ch3
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0xB0);
+ _data2=_spi.write(0x00);
+ int ch3 =(_data1<<8) | _data2;
+ ch3 = ch3 & 0x03FF;
+ cs=1;
+
+
+//ch4
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0xC0);
+ _data2=_spi.write(0x00);
+ int ch4 =(_data1<<8) | _data2;
+ ch4 = ch4 & 0x03FF;
+ cs=1;
+
+
+//ch5
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0xD0);
+ _data2=_spi.write(0x00);
+ int ch5 =(_data1<<8) | _data2;
+ ch5 = ch5 & 0x03FF;
+ cs=1;
+
+
+//ch6
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0xE0);
+ _data2=_spi.write(0x00);
+ int ch6 =(_data1<<8) | _data2;
+ ch6 = ch6 & 0x03FF;
+ cs=1;
+
+
+//ch7
+ cs=0;
+ _spi.write(0x01);
+ _data1=_spi.write(0xF0);
+ _data2=_spi.write(0x00);
+ int ch7 =(_data1<<8) | _data2;
+ ch7 = ch7 & 0x03FF;
+ cs=1;
+
+
+//Display the results
+ lcd.cls();
+ lcd.locate(0,0);
+ lcd.printf("%d%d%d%d",ch0,ch1,ch2,ch3);
+ lcd.locate(0,1);
+ lcd.printf("%d%d%d%d",ch4,ch5,ch6,ch7);
+
+ wait(0.01);
+ }
+}
+
diff -r 000000000000 -r c4617b633a1e mbed.bld --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Fri Feb 26 18:16:20 2010 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/49a220cc26e0