不韋 呂
/
OpenCampus_FreqConv
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Diff: AnalogIO_1ch/MCP4921.cpp
- Revision:
- 0:f69d3c64978d
- Child:
- 1:d8449dbcde02
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/AnalogIO_1ch/MCP4921.cpp Mon Jul 28 07:30:22 2014 +0000
@@ -0,0 +1,43 @@
+//------------------------------------------------------
+// Class for 1 DAC in MCO4922
+//
+// 2014/07/18, Copyright (c) 2014 MIKAMI, Naoki
+//------------------------------------------------------
+
+#include "MCP4921.hpp"
+
+namespace Mikami
+{
+ DacMCP4921::DacMCP4921(PinName mosi, PinName sclk,
+ PinName cs, int hz)
+ : mySpi_(mosi, NC, sclk, PA_4), myCs_(cs, 1)
+ {
+ // Set SPI format and bus frequency
+ mySpi_.format(16, 0);
+ mySpi_.frequency(hz);
+
+ // Set DAC to 0
+ WriteDac(0);
+ }
+
+ void DacMCP4921::Write(float value)
+ {
+ if (value < -1.0f) value = -1.0f;
+ if (value > 1.0f) value = 1.0f;
+
+ WriteDac((uint16_t)((value + 1.0f)*2047));
+ }
+
+ void DacMCP4921::Write(uint16_t value)
+ {
+ WriteDac((value > 4095) ? 4095 : value);
+ }
+
+ void DacMCP4921::WriteDac(uint16_t value)
+ {
+ myCs_.write(0); // cs <= L
+ mySpi_.write(value | 0x3000);
+ myCs_.write(1); // cs <= H
+ }
+}
+