Merge pull request 'add max1227 module' (#145) from mueller/max1227-module into develop

Reviewed-on: #145
Reviewed-by: Jakob.Meier <meierj@irs.uni-stuttgart.de>

mission/devices/CMakeLists.txt

@@ -16,6 +16,5 @@ target_sources(${LIB_EIVE_MISSION} PRIVATE
     RadiationSensorHandler.cpp
     GyroADIS1650XHandler.cpp
     RwHandler.cpp
+    max1227.cpp
 )
-
-

mission/devices/max1227.cpp

@@ -0,0 +1,28 @@
+#include "max1227.h"
+
+#include <cstring>
+
+void max1227::prepareExternallyClockedSingleChannelRead(uint8_t *spiBuf, uint8_t channel,
+                                                        size_t &sz) {
+  spiBuf[0] = buildConvByte(ScanModes::N_ONCE, channel, false);
+  spiBuf[1] = 0x00;
+  spiBuf[2] = 0x00;
+  sz = 3;
+}
+
+void max1227::prepareExternallyClockedRead0ToN(uint8_t *spiBuf, uint8_t n, size_t &sz) {
+  for (uint8_t idx = 0; idx <= n; idx++) {
+    spiBuf[idx * 2] = buildConvByte(ScanModes::N_ONCE, idx, false);
+    spiBuf[idx * 2 + 1] = 0x00;
+  }
+  spiBuf[(n + 1) * 2] = 0x00;
+  sz += (n + 1) * 2 + 1;
+}
+
+void max1227::prepareExternallyClockedTemperatureRead(uint8_t *spiBuf, size_t &sz) {
+  spiBuf[0] = buildConvByte(ScanModes::N_ONCE, 0, true);
+  std::memset(spiBuf + 1, 0, 24);
+  sz += 25;
+}
+
+float max1227::getTemperature(int16_t temp) { return static_cast<float>(temp) * 0.125; }

mission/devices/max1227.h

@@ -0,0 +1,84 @@
+#ifndef MISSION_DEVICES_MAX1227_H_
+#define MISSION_DEVICES_MAX1227_H_
+
+#include <cstddef>
+#include <cstdint>
+
+namespace max1227 {
+
+enum ScanModes : uint8_t {
+  CHANNELS_0_TO_N = 0b00,
+  CHANNEL_N_TO_HIGHEST = 0b01,
+  N_REPEATEDLY = 0b10,
+  N_ONCE = 0b11
+};
+
+enum ClkSel : uint8_t {
+  INT_CONV_INT_TIMED_CNVST_AS_CNVST = 0b00,
+  INT_CONV_EXT_TIMED_CNVST = 0b01,
+  // Default mode upon power-up
+  INT_CONV_INT_TIMED_CNVST_AS_AIN = 0b10,
+  // Use external SPI clock for conversion and timing
+  EXT_CONV_EXT_TIMED = 0b11
+};
+
+enum RefSel : uint8_t {
+  INT_REF_WITH_WAKEUP = 0b00,
+  // No wakeup delay needed
+  EXT_REF_SINGLE_ENDED = 0b01,
+  INT_REF_NO_WAKEUP = 0b10,
+  // No wakeup delay needed
+  EXT_REF_DIFFERENTIAL = 0b11
+};
+
+enum DiffSel : uint8_t {
+  NONE_0 = 0b00,
+  NONE_1 = 0b01,
+  // One unipolar config byte follows the setup byte
+  UNIPOLAR_CFG = 0b10,
+  // One bipolar config byte follows the setup byte
+  BIPOLAR_CFG = 0b11
+};
+
+constexpr uint8_t buildResetByte(bool fifoOnly) { return (1 << 4) | (fifoOnly << 3); }
+
+constexpr uint8_t buildConvByte(ScanModes scanMode, uint8_t channel, bool readTemp) {
+  return (1 << 7) | (channel << 3) | (scanMode << 1) | readTemp;
+}
+
+constexpr uint8_t buildSetupByte(ClkSel clkSel, RefSel refSel, DiffSel diffSel) {
+  return (1 << 6) | (clkSel << 4) | (refSel << 2) | diffSel;
+}
+
+/**
+ * If there is a wakeup delay, there needs to be a 65 us delay between sending
+ * the first byte (conversion byte) and the the rest of the SPI buffer.
+ * The raw ADC value will be located in the first and second reply byte.
+ * @param spiBuf
+ * @param n
+ * @param sz
+ */
+void prepareExternallyClockedSingleChannelRead(uint8_t* spiBuf, uint8_t channel, size_t& sz);
+
+/**
+ * If there is a wakeup delay, there needs to be a 65 us delay between sending
+ * the first byte (first conversion byte) the the rest of the SPI buffer.
+ * @param spiBuf
+ * @param n Channel number. Example: If the ADC has 6 channels, n will be 5
+ * @param sz
+ */
+void prepareExternallyClockedRead0ToN(uint8_t* spiBuf, uint8_t n, size_t& sz);
+
+/**
+ * Prepare an externally clocked temperature read. 25 bytes have to be sent
+ * and the raw temperature value will appear on the last 2 bytes of the reply.
+ * @param spiBuf
+ * @param sz
+ */
+void prepareExternallyClockedTemperatureRead(uint8_t* spiBuf, size_t& sz);
+
+float getTemperature(int16_t temp);
+
+}  // namespace max1227
+
+#endif /* MISSION_DEVICES_MAX1227_H_ */