Use mailbox for thread-safe data transfer, Improve SPI reliability

documentation/masterboard_communication.md

@@ -16,28 +16,22 @@ On the 4 pairs of wires, only 2 are used by the ethernet 100Mbps and cables are
 
 It is possible to make the ethernet cables lighter by using only 2 twisted pairs of wire. The wires can be attached to the power cables without any issues of packet loss.
 
-For reference, here is the wiring:
-
 On a Straight cable, keep the orange wires (1,2) and green wires (3,6).
-
-Do not untwist the wires!
-
-![straight-through-cable](https://www.fs.com/images/ckfinder/ftp_images/tutorial/straight-through-cable.png)
-
+Do not untwist the wires.
 
 WiFi
 ----
 The WiFi connection is also happening at the lowest level of the 802.11 specification, using vendor specific action frame. No base station or rooter are needed. No identification is needed.
 
-Ideally a free channel should be used, with a minimum of 2.4Ghz devices surrounding. TODO setup a procedure to change the master board channel, currently hard-coded in the firmware.
+Ideally a free channel should be used, with a minimum of 2.4Ghz devices surrounding. The master board will automaticaly detect the chanel used at startup.
 
 The interface on the PC needs to support monitor mode and injection. ASUS PCE-AC51 has been tested with a RT Preempt patched OS.
 
 
 Data packet
 -----------
 
-### Current protocol version: **3**
+### Current protocol version: **4**
 
 Both WiFi and Ethernet use the same data packet format.
 
@@ -58,17 +52,21 @@ Session ID | SPI connected
 --- | --- 
 2 bytes | 1 byte
 
-The **SPI connected** field contains an 8 bit integer, each bit of which tells whether or not the corresponding SPI slave is connected (Least significant bit: SPI0, most significant bit: SPI7).
 
+
+The **SPI connected** field contains an 8 bit integer, each bit of which tells whether or not the corresponding SPI slave is connected (Least significant bit: SPI0, most significant bit: SPI7).
+### Packets
 Both **Command** and **Sensor** packets encapsulate 6 BLMC µDriver SPI interface packets,  without the **Index** and **CRC** fields. Additional, sensor packets also include IMU measurement and AHRS estimation.
 
-### Sensor packet (200 Bytes)
-Session ID | µDriver0 | µDriver1 | µDriver2 | µDriver3 | µDriver4 | µDriver5 | IMU | Sensor Index | Packet Loss | Last Command Index
---- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
-2 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 24 Bytes | 2 Bytes | 2 Bytes | 2 Bytes
+### Sensor packet (212 Bytes)
+Session ID | µDriver0 | µDriver1 | µDriver2 | µDriver3 | µDriver4 | µDriver5 | IMU | Power Board |Sensor Index | Packet Loss | Last Command Index
+--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
+2 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 28 Bytes | 24 Bytes | 12 Bytes | 2 Bytes | 2 Bytes | 2 Bytes
 
 **µDriverX** corresponds to a BLMC µDriver SPI interface sensor packet without the CRC and index fields.
 
+**Power Board** correspond the powerboard measurment data composed of bus current, voltage and energy.
+
 **IMU** is composed of Accelerometer, Gyroscope, AHRS, and estimation of Linear Acceleration (without gravity) data:
 
 AccX | AccY | AccZ | GyrX | GyrY | GyrZ | AHRS Roll | AHRS Pitch | AHRS Yaw | LinAccX | LinAccY | LinAccZ

firmware/components/quad_crc/quad_crc.c

@@ -82,4 +82,25 @@ uint32_t CRC_compute(uint8_t *bytes, int len) {
 
 bool CRC_check(uint8_t *bytes, int len) {
     return (CRC_compute(bytes, len) == 0);
+}
+
+
+uint16_t crc16_ccitt(uint8_t * data, int len)
+{
+    uint16_t crc = 0xFFFF;
+    for (unsigned int i = 0; i < len; ++i) {
+        uint16_t dbyte = data[i];
+        crc ^= dbyte << 8;
+        for (uint8_t j = 0; j < 8; ++j) {
+            uint16_t mix = crc & 0x8000;
+            crc = (crc << 1);
+            if (mix)
+                crc = crc ^ 0x1021;
+        }
+    }
+    return crc;
+}
+
+bool crc16_ccitt_check(uint8_t * data, int len){
+    return (crc16_ccitt(data, len) == 0);
 }

firmware/components/quad_crc/quad_crc.h

@@ -6,5 +6,6 @@
 
 bool CRC_check(uint8_t *bytes, int len);
 uint32_t CRC_compute(uint8_t *bytes, int len);
-
+uint16_t crc16_ccitt(uint8_t * data, int len);
+bool crc16_ccitt_check(uint8_t * data, int len);
 #endif

firmware/main/defines.h

@@ -3,8 +3,12 @@
 
 #include <stdint.h>
 
-#define PROTOCOL_VERSION 3
+#define PROTOCOL_VERSION 4
 
+union floatbytes{
+    float f;
+    uint8_t b[4];
+};
 struct sensor_data {
 	uint16_t status;
 	uint16_t timestamp;
@@ -32,6 +36,12 @@ struct imu_data {
 	int16_t linear_acceleration[3];
 } __attribute__((packed));
 
+struct powerboard_data {
+    uint16_t vbus;
+    int16_t vshunt;
+    float energy;
+} __attribute__((packed));
+
 struct wifi_eth_packet_init {
 	uint16_t protocol_version; // used to ensure both the interface and the firmware use the same protocol
 	uint16_t session_id;
@@ -53,6 +63,7 @@ struct wifi_eth_packet_sensor {
 	uint16_t session_id;
     struct sensor_data sensor[CONFIG_N_SLAVES];
     struct imu_data imu;
+    struct powerboard_data powerboard;
     uint16_t sensor_index;
     uint16_t packet_loss;
 	uint16_t last_cmd_index;

firmware/main/masterboard_main.c

@@ -347,6 +347,22 @@ static void periodic_timer_callback(void *arg)
                 wifi_eth_tx_data.sensor[i].status = 0xf; // specifying that the transaction failed in the sensor packet
             }
         }
+
+        //Slave 7 is always the power board
+        uint8_t tx_spi_powerboard[12]={0xaa,0xbb,0xcc,0xdd,0xee,0xff,0xaa,0xbb,0xcc,0xdd,0xee,0xff}; //Fake packet, cmd to the power board are not yet implemented
+        uint8_t rx_spi_powerboard[12]={0};
+        spi_send(7, tx_spi_powerboard,rx_spi_powerboard, 12);
+        if (crc16_ccitt_check(rx_spi_powerboard,12)) //Packet valid?
+        {
+            wifi_eth_tx_data.powerboard.vbus = (rx_spi_powerboard[2]<<8) | rx_spi_powerboard[3];
+            wifi_eth_tx_data.powerboard.vshunt = (rx_spi_powerboard[4]<<8) | rx_spi_powerboard[5];
+            union floatbytes fb;
+            fb.b[3] = rx_spi_powerboard[6];
+            fb.b[2] = rx_spi_powerboard[7];
+            fb.b[1] = rx_spi_powerboard[8];
+            fb.b[0] = rx_spi_powerboard[9];
+            wifi_eth_tx_data.powerboard.energy = fb.f;
+        }
     }
 
     /* Get IMU latest data*/