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--- projects:crazyflie:crtp [2013-02-22 07:21]
macke
+++ projects:crazyflie:crtp [2021-06-24 16:48] (current)
kimberly
@@ Line 1: / Line 1: @@
+<WRAP center round important 60%>
+This page has deprecated and will be archived. Please go to [[https://www.bitcraze.io/]].
+</WRAP>
 ====== Crazy RealTime Protocol ======
 The protocol used to communicate with the Crazyflie is called the Crazy RealTime Protocol, or CRTP in short. It's a simple protocol mainly designed to suit the radio chip used on the Crazyflie but the protocol can also be used on other physical links.
@@ Line 22: / Line 25: @@
 CRTP is implemented in 3 layers:
-<code>
+<ditaa>
  +-----------------------+
  |   Application/ports   |
@@ Line 30: / Line 33: @@
  |       CRTP Link       |
  +-----------------------+
-</code>
+</ditaa>
   * **CRTP Link** is responsible for transferring the packets between the Crazyflie and the host. It will typically handles packet size and error detection.
@@ Line 41: / Line 44: @@
 ^  **Port**  ^   **Target**   ^  **Used for**   ^
 |   0        |   [[projects:crazyflie:crtp:console | Console ]]      | Read console text that is printed to the console on the Crazyflie using consoleprintf |
-|   2        |   [[projects:crazyflie:crtp:param | Parameters]]   | Get/set parameters from the Crazyflie. Parameters are defined using a macro in the Crazyflie source-code |
+|   2        |   [[projects:crazyflie:crtp:param | Parameters]]   | Get/set parameters from the Crazyflie. Parameters are defined using a [[projects:crazyflie:firmware:param|macro in the Crazyflie source-code]] |
 |   3        |   [[projects:crazyflie:crtp:commander |Commander]]    | Sending control set-points for the roll/pitch/yaw/thrust regulators |
-|   5        |   [[projects:crazyflie:crtp:log#|Log]]    | Set up log blocks with variables that will be sent back to the Crazyflie at a specified period. Log variables are defined using a macro in the Crazyflie source-code |
+|   5        |   [[projects:crazyflie:crtp:log#|Log]]    | Set up log blocks with variables that will be sent back to the Crazyflie at a specified period. Log variables are defined using a [[projects:crazyflie:firmware:log|macro in the Crazyflie source-code]] |
+|   7        |   [[projects:crazyflie:crtp:setpointgeneric | Setpoint Generic]] | For sending generic, extensible setpoints |
 |   14       |   [[projects:crazyflie:pc_utils:debugdriver|Client-side debugging]]    | Debugging the UI and exists only in the Crazyflie Python API and not in the Crazyflie itself.  |
 |   15       |   [[projects:crazyflie:crtp:linklayer |Link layer ]]   | Used to control and query the communication link |
@@ Line 56: / Line 60: @@
 ===== Serial port =====
-This is mostly for legacy support but has been used during development to log data at higher speeds. The support for using the serial port might be broken currently though.
+The serial port is configured in 115200 8N1. CRTP packets are sent and received asynchronously using the following packet format:
 <code>
+   6   5   4   3   2   1   0
++---+---+---+---+---+---+---+---+
+|             0xAA              |
++---+---+---+---+---+---+---+---+
+|             0xAA              |
++---+---+---+---+---+---+---+---+
+|      Port     |  Res  | Chan. |
++---+---+---+---+---+---+---+---+
+|         Packet length         |
++---+---+---+---+---+---+---+---+
+|            DATA 0             |
++---+---+---+---+---+---+---+---+
+:   :   :   :   :   :   :   :   :
++---+---+---+---+---+---+---+---+
+|            Cksum              |
++---+---+---+---+---+---+---+---+
 +--------+--------+--------+--------+--------+--....--+--------+
-|  0xAA  |  0xAA  | Header | Length | Data0  | Packet | CRC32  |
+|  0xAA  |  0xAA  | Header | Length | Data0  | Packet | Cksum  |
 +--------+--------+--------+--------+--------+--....--+--------+
 </code>
-^ **Field** ^ **Byte** ^     **Description**     ^
+^ **Field** ^ **Byte** ^ **Bit** ^     **Description**     ^
-|   Start   |    0-1   | Start token for synchronization (0xAAAA)  |
+|   Start   |    0-1   |   0-2   | Start token for synchronization (0xAAAA)  |
-|   Header  |     2    | The destination channel  |
+|   Header  |     2    |   0-1   | The destination channel  |
-|    Size   |     3    | The size of the packet |
+|    :::    |     2    |   2-3   | Reserved for the link layer |
-|    Data   |    4-34  | The data in the packet |
+|    :::    |     2    |   4-7   | The destination port  |
-|    CRC    |   35-36  | The CRC16 of the packet |
+|    Size   |     3    |         | Number of data byte |
+|    Data   |    4-..  |         | The data in the packet |
+|   Cksum   |  4+size  |         | Checksum. Sum of all the bytes, excluding //Start//, modulo 256. |
+==== Example ====
+To send setpoints to the [[projects:crazyflie:crtp:commander|commander]] send:
+<code>
+xaa 0xaa 0x30 0x0e 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x3e
+</code>
+To ping Crazyflie:
+<code>
+ ->   0xaa 0xaa 0xf0 0x01 0x01 0xf2     # Sent to the copter
+ <-   0xaa 0xaa 0xf0 0x01 0x01 0xf2     # Received from the copter
+</code>

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