From 55b09635fbf3870082b08572f460d5d84c86ccdc Mon Sep 17 00:00:00 2001
From: Jake Drahos <j@kedrahos.com>
Date: Sun, 29 Jan 2017 21:13:56 -0600
Subject: [PATCH] Began writing header files for common
---
groundStation/src/backend/common/controller.h | 29 ++++++++
groundStation/src/backend/common/examples.c | 72 +++++++++++++++++++
groundStation/src/backend/common/packet.h | 33 +++++++++
groundStation/src/backend/common/setcontrol.h | 27 +++++++
4 files changed, 161 insertions(+)
create mode 100644 groundStation/src/backend/common/controller.h
create mode 100644 groundStation/src/backend/common/examples.c
create mode 100644 groundStation/src/backend/common/packet.h
create mode 100644 groundStation/src/backend/common/setcontrol.h
diff --git a/groundStation/src/backend/common/controller.h b/groundStation/src/backend/common/controller.h
new file mode 100644
index 000000000..8c88147c2
--- /dev/null
+++ b/groundStation/src/backend/common/controller.h
@@ -0,0 +1,29 @@
+#ifndef _controller_h
+#define _controller_h
+
+enum ControllerID {
+ ROLL_ID, // 00 - Roll PID
+ PITCH_ID, // 01 - Pitch PID
+ YAW_ID, // 02 - Yaw PID
+ ROLL_RATE_ID, // 03 - Roll rate PID
+ PITCH_RATE_ID, // 04 - Pitch rate PID
+ YAW_RATE_ID, // 05 - Yaw rate PID
+ LOCAL_X_ID, // 06 - Local X PID
+ LOCAL_Y_ID, // 07 - Local Y PID
+ ALT_ID, // 08 - Altitude PID
+};
+
+enum ControllerValueID{
+ KP_ID, // 00 - P constant
+ KI_ID, // 01 - I constant
+ KD_ID, // 02 - D constant
+ SP_ID, // 03 - Setpoint value
+};
+
+struct controller_message {
+ enum ControllerID id;
+ enum ControllerValueID value_id;
+ float value;
+};
+
+#endif
diff --git a/groundStation/src/backend/common/examples.c b/groundStation/src/backend/common/examples.c
new file mode 100644
index 000000000..7d0ee50ae
--- /dev/null
+++ b/groundStation/src/backend/common/examples.c
@@ -0,0 +1,72 @@
+#include "packet.h"
+#include "setcontrol.h"
+#include "commands.h"
+
+#include <sys/types.h>
+
+static int next_msg_id = 0;
+
+int SendSetControl()
+{
+ struct metadata m;
+ struct controller_message cm;
+
+ cm.id = ROLL_ID; /* Roll controller */
+ cm.value_id = KI_ID; /* I coefficient */
+ cm.value = 42.00f; /* An appropriate value */
+
+ uint8_t data[64];
+ m.msg_id = next_msg_id++;
+ /* Fills in the rest of the metadata automatically */
+ if (EncodeSetcontrol(&m, data, 64, &cm) < 0) {
+ return -1;
+ }
+
+ uint8_t packet[128];
+ ssize_t length;
+ if ((length = EncodePacket(packet, 128, &m, data)) < 0) {
+ return -1;
+ }
+
+ /* Now you can send the packet
+ * sendThePacket(packet, length);
+ */
+
+ return 0;
+}
+
+
+/* Process incoming packets */
+int receive_packet(uint8_t * packet, size_t length)
+{
+ struct metadata m;
+ uint8_t data[128];
+
+ /* Will fail if checksum is bad, etc */
+ if (DecodePacket(&m, data, 128, packet, length) < 0) {
+ return -1;
+ }
+
+ /* Let's pretend that the callbacks have signature
+ * void cb(
+ * const struct metadata * m,
+ * const uint8_t * data);
+ *
+ * Call the callback.
+ */
+ (*MessageTypes[m.msg_type].functionPtr)(&m, data);
+
+ return 0;
+}
+
+/* An example of a setcontrol callback. Arguments
+ * aren't important, as long as we have access
+ * to the packet bytes and the length
+ */
+void cb_setcontrol(const struct metadata *m, const uint8_t *data)
+{
+ struct controller_message cm;
+ DecodeSetcontrol(&cm, m, data);
+
+ /* cm now has populated controller ID, value ID, and value */
+}
diff --git a/groundStation/src/backend/common/packet.h b/groundStation/src/backend/common/packet.h
new file mode 100644
index 000000000..2763a8036
--- /dev/null
+++ b/groundStation/src/backend/common/packet.h
@@ -0,0 +1,33 @@
+#ifndef _packet_h
+#define _packet_h
+
+#include <stdint.h>
+#include <sys/types.h>
+
+struct metadata {
+ int msg_type;
+ int msg_id;
+ int data_len;
+};
+
+/* Combine metadata and data to form a wire-sendable packet.
+ * Returns the size of the encoded packet
+ */
+ssize_t EncodePacket(
+ uint8_t * packet, /* Buffer to encode into */
+ size_t packet_size, /* Max buffer size */
+ const struct metadata * m, /* Metadata to encode */
+ const uint8_t * data); /* Data to encode */
+
+/* Break apart packet, populating metadata. Data is copied
+ * into the space pointed to by data.
+ * Returns the size of the data.
+ */
+ssize_t DecodePacket(
+ struct metadata * m, /* Decoded metadata (includes data_len)*/
+ uint8_t * data, /* Data is copied into this buffer */
+ size_t data_size, /* Max buffer size */
+ const uint8_t * packet, /* Packet to decode */
+ size_t packet_size); /* Size of packet to decode */
+
+#endif
diff --git a/groundStation/src/backend/common/setcontrol.h b/groundStation/src/backend/common/setcontrol.h
new file mode 100644
index 000000000..b7f880bce
--- /dev/null
+++ b/groundStation/src/backend/common/setcontrol.h
@@ -0,0 +1,27 @@
+#ifndef _setcontrol_h
+#define _setcontrol_h
+
+#include "packet.h"
+#include "controller.h"
+
+#include <sys/types.h>
+
+/* Creates data and metadata for a setcontrol packet
+ * Returns data size.
+ */
+ssize_t EncodeSetcontrol(
+ struct metadata * m, /* data_len and msg_type will be populated*/
+ uint8_t * data, /* Output buffer */
+ size_t data_size, /* Max buffer size */
+ const struct controller_message * cm); /* Message to encode */
+
+/* Decode a metadata and data to populate a controller.
+ * Returns 0 on success, -1 on failure.
+ */
+int DecodeSetcontrol(
+ struct controller_message * cm, /* Decoded controller message */
+ const struct metadata * m, /* Metadata to aid in decoding */
+ const uint8_t * data); /* Data to decode */
+
+
+#endif
--
GitLab