Added support for STA5635 SPI command/response. (#341)

# New Features
- Added message support for sending SPI commands over a UART to an
STA5635 L-band front end

BUILD

@@ -63,6 +63,17 @@ cc_library(
     ],
 )
 
+# STA5635 RF front-end message definitions.
+cc_library(
+    name = "sta5635",
+    hdrs = [
+        "src/point_one/fusion_engine/messages/sta5635.h",
+    ],
+    deps = [
+        ":core_headers",
+    ],
+)
+
 # ROS translation message definitions.
 cc_library(
     name = "ros_support",

python/fusion_engine_client/messages/__init__.py

@@ -1,6 +1,7 @@
 from .core import *
 from .fault_control import *
 from . import ros
+from . import sta5635
 
 message_type_to_class = MessagePayload.message_type_to_class
 message_type_by_name = MessagePayload.message_type_by_name

python/fusion_engine_client/messages/defs.py

@@ -154,6 +154,9 @@ class MessageType(IntEnum):
 
     LBAND_FRAME = 14000
 
+    STA5635_COMMAND = 14100
+    STA5635_COMMAND_RESPONSE = 14101
+
     RESERVED = 20000
 
     @classmethod

python/fusion_engine_client/messages/sta5635.py

@@ -0,0 +1,86 @@
+from construct import (Struct, Int8ul, Int32ul, Int64sl, Bytes)
+
+from ..utils.construct_utils import construct_message_to_string
+from .defs import *
+
+
+class STA5635Command(MessagePayload):
+    """!
+    @brief A command to be sent to an attached STA5635 RF front-end.
+    """
+    MESSAGE_TYPE = MessageType.STA5635_COMMAND
+    MESSAGE_VERSION = 0
+
+    Construct = Struct(
+        "command" / Int8ul,
+        "address" / Int8ul,
+        "data" / Bytes(2),
+    )
+
+    def __init__(self):
+        self.command = 0
+        self.address = 0
+        self.data = bytes()
+
+    def pack(self, buffer: Optional[bytes] = None, offset: int = 0, return_buffer: bool = True) -> (bytes, int):
+        values = vars(self)
+        packed_data = self.Construct.build(values)
+        return PackedDataToBuffer(packed_data, buffer, offset, return_buffer)
+
+    def unpack(self, buffer: bytes, offset: int = 0, message_version: int = MessagePayload._UNSPECIFIED_VERSION) -> int:
+        parsed = self.Construct.parse(buffer[offset:])
+        self.__dict__.update(parsed)
+        del self.__dict__['_io']
+        return parsed._io.tell()
+
+    def calcsize(self) -> int:
+        return self.Construct.sizeof()
+
+    def __repr__(self):
+        result = super().__repr__()[:-1]
+        result += f', command=0x{self.command:02X}, address=0x{self.address:02X}, data={self.data}]'
+        return result
+
+    def __str__(self):
+        return construct_message_to_string(message=self, value_to_string={
+            'command': lambda x: f'0x{x:02X}',
+            'address': lambda x: f'0x{x:02X}',
+        })
+
+
+class STA5635CommandResponse(MessagePayload):
+    """!
+    @brief Result from an STA5635 sent in response to an @ref STA5635Command.
+    """
+    MESSAGE_TYPE = MessageType.STA5635_COMMAND_RESPONSE
+    MESSAGE_VERSION = 0
+
+    Construct = Struct(
+        "system_time_ns" / Int64sl,
+        "command_sequence_number" / Int32ul,
+        "data" / Bytes(4),
+    )
+
+    def __init__(self):
+        self.system_time_ns = 0
+        self.command_sequence_number = 0
+        self.data = bytes()
+
+    def pack(self, buffer: Optional[bytes] = None, offset: int = 0, return_buffer: bool = True) -> (bytes, int):
+        values = vars(self)
+        packed_data = self.Construct.build(values)
+        return PackedDataToBuffer(packed_data, buffer, offset, return_buffer)
+
+    def unpack(self, buffer: bytes, offset: int = 0, message_version: int = MessagePayload._UNSPECIFIED_VERSION) -> int:
+        parsed = self.Construct.parse(buffer[offset:])
+        self.__dict__.update(parsed)
+        del self.__dict__['_io']
+        return parsed._io.tell()
+
+    def calcsize(self) -> int:
+        return self.Construct.sizeof()
+
+    def __repr__(self):
+        result = super().__repr__()[:-1]
+        result += f', seq={self.command_sequence_number}, data={self.data}]'
+        return result

src/point_one/fusion_engine/messages/defs.h

@@ -104,8 +104,11 @@ enum class MessageType : uint16_t {
 
   LBAND_FRAME = 14000, ///< @ref LBandFrameMessage
 
+  STA5635_COMMAND = 14100, ///< @ref STA5635Command
+  STA5635_COMMAND_RESPONSE = 14101, ///< @ref STA5635CommandResponse
+
   /// The maximum defined @ref MessageType enum value.
-  MAX_VALUE = LBAND_FRAME,
+  MAX_VALUE = STA5635_COMMAND_RESPONSE,
 };
 
 /**
@@ -272,6 +275,12 @@ P1_CONSTEXPR_FUNC const char* to_string(MessageType type) {
 
     case MessageType::LBAND_FRAME:
       return "L-band Frame Contents";
+
+    case MessageType::STA5635_COMMAND:
+      return "STA5635 Command";
+
+    case MessageType::STA5635_COMMAND_RESPONSE:
+      return "STA5635 Command Response";
   }
   return "Unrecognized Message";
 }
@@ -309,6 +318,7 @@ P1_CONSTEXPR_FUNC bool IsCommand(MessageType message_type) {
     case MessageType::EXPORT_DATA:
     case MessageType::SET_MESSAGE_RATE:
     case MessageType::GET_MESSAGE_RATE:
+    case MessageType::STA5635_COMMAND:
       return true;
     case MessageType::INVALID:
     case MessageType::POSE:
@@ -348,6 +358,7 @@ P1_CONSTEXPR_FUNC bool IsCommand(MessageType message_type) {
     case MessageType::MESSAGE_RATE_RESPONSE:
     case MessageType::SUPPORTED_IO_INTERFACES:
     case MessageType::LBAND_FRAME:
+    case MessageType::STA5635_COMMAND_RESPONSE:
       return false;
   }
   return false;
@@ -368,6 +379,7 @@ P1_CONSTEXPR_FUNC bool IsResponse(MessageType message_type) {
     case MessageType::COMMAND_RESPONSE:
     case MessageType::CONFIG_RESPONSE:
     case MessageType::MESSAGE_RATE_RESPONSE:
+    case MessageType::STA5635_COMMAND_RESPONSE:
       return true;
     default:
       return false;

src/point_one/fusion_engine/messages/sta5635.h

@@ -0,0 +1,90 @@
+/**************************************************************************/ /**
+ * @brief Command/control support for an attached STA5635 RF front-end.
+ * @file
+ ******************************************************************************/
+
+#pragma once
+
+#include "point_one/fusion_engine/common/portability.h"
+#include "point_one/fusion_engine/messages/defs.h"
+
+namespace point_one {
+namespace fusion_engine {
+namespace messages {
+
+// Enforce 4-byte alignment and packing of all data structures and values.
+// Floating point values are aligned on platforms that require it. This is done
+// with a combination of setting struct attributes, and manual alignment
+// within the definitions. See the "Message Packing" section of the README.
+#pragma pack(push, 1)
+
+/**************************************************************************/ /**
+ * @defgroup sta5635 STA5635 Command/Control Messages
+ * @brief Messages for interacting with an attached STA5635 RF front-end device.
+ * @ingroup device_control
+ *
+ * These messages are intended to be used only for devices with an
+ * STMicroelectronics STA5635 RF front-end where direct user control of the
+ * front-end is needed. This is not common and should not be used on most
+ * platforms.
+ *
+ * For platforms using an STA5635, the device will output @ref LBandFrameMessage
+ * containing I/Q samples from the RF front-end. The format and use of the I/Q
+ * samples is platform-specific.
+ *
+ * See also @ref messages.
+ ******************************************************************************/
+
+/**
+ * @brief A command to be sent to an attached STA5635 RF front-end. (@ref
+ *        MessageType::STA5635_COMMAND, version 1.0).
+ * @ingroup sta5635
+ *
+ * See the STA5635 data sheet for the allowed command, address, and data values.
+ */
+struct P1_ALIGNAS(4) STA5635Command : public MessagePayload {
+  static constexpr MessageType MESSAGE_TYPE = MessageType::STA5635_COMMAND;
+  static constexpr uint8_t MESSAGE_VERSION = 0;
+
+  /** The STA5635 command code to be issued. */
+  uint8_t command = 0;
+  /** The address of the STA5635 register to be accessed. */
+  uint8_t address = 0;
+  /**
+   * The value to be sent to the device, where `data[0]` contains the MSB.
+   */
+  uint8_t data[2] = {0};
+};
+
+/**
+ * @brief Result from an STA5635 sent in response to an @ref STA5635Command.
+ *        (@ref MessageType::STA5635_COMMAND_RESPONSE, version 1.0).
+ * @ingroup sta5635
+ */
+struct P1_ALIGNAS(4) STA5635CommandResponse : public MessagePayload {
+  static constexpr MessageType MESSAGE_TYPE =
+      MessageType::STA5635_COMMAND_RESPONSE;
+  static constexpr uint8_t MESSAGE_VERSION = 0;
+
+  /**
+   * The system time when the response was received (in nanoseconds). Note that
+   * this is not synchronized to P1 or GNSS time.
+   */
+  int64_t system_time_ns = 0;
+  /**
+   * The sequence number contained in the @ref STA5635Command to which this
+   * response belongs.
+   */
+  uint32_t command_sequence_number = 0;
+  /**
+   * The response from the device, where `data[0]` contains the first byte in
+   * the response.
+   */
+  uint8_t data[4] = {0};
+};
+
+#pragma pack(pop)
+
+} // namespace messages
+} // namespace fusion_engine
+} // namespace point_one