various new ideas in README.md. Making hoverserial start from zero speed and highlighting that it will trigger backward beeps.

Author: lsisoft

Arduino/hoverserial/hoverserial.ino

@@ -11,6 +11,8 @@
 //   it is recommended to use the built-in Serial interface for full speed perfomace.
 // • The data packaging includes a Start Frame, checksum, and re-syncronization capability for reliable communication
 // 
+// The code starts with zero speed and moves towards +
+//
 // CONFIGURATION on the hoverboard side in config.h:
 // • Option 1: Serial on Right Sensor cable (short wired cable) - recommended, since the USART3 pins are 5V tolerant.
 //   #define CONTROL_SERIAL_USART3
@@ -28,6 +30,7 @@
 #define START_FRAME         0xABCD     	// [-] Start frme definition for reliable serial communication
 #define TIME_SEND           100         // [ms] Sending time interval
 #define SPEED_MAX_TEST      300         // [-] Maximum speed for testing
+#define SPEED_STEP          20          // [-] Speed step
 // #define DEBUG_RX                        // [-] Debug received data. Prints all bytes to serial (comment-out to disable)
 
 #include <SoftwareSerial.h>
@@ -146,8 +149,8 @@ void Receive()
 // ########################## LOOP ##########################
 
 unsigned long iTimeSend = 0;
-int iTestMax = SPEED_MAX_TEST;
 int iTest = 0;
+int iStep = SPEED_STEP;
 
 void loop(void)
 { 
@@ -159,11 +162,14 @@ void loop(void)
   // Send commands
   if (iTimeSend > timeNow) return;
   iTimeSend = timeNow + TIME_SEND;
-  Send(0, SPEED_MAX_TEST - 2*abs(iTest));
+  Send(0, iTest);
 
   // Calculate test command signal
-  iTest += 10;
-  if (iTest > iTestMax) iTest = -iTestMax;
+  iTest += iStep;
+
+  // invert step if reaching limit
+  if (iTest >= SPEED_MAX_TEST || iTest <= -SPEED_MAX_TEST)
+    iStep = -iStep;
 
   // Blink the LED
   digitalWrite(LED_BUILTIN, (timeNow%2000)<1000);

README.md

@@ -144,7 +144,9 @@ With slight modifications in config.h, other dual-inputs combinations can be rea
 ---
 ## Flashing
 
-Right to the STM32, there is a debugging header with GND, 3V3, SWDIO and SWCLK. Connect GND, SWDIO and SWCLK to your SWD programmer, like the ST-Link found on many STM devboards.
+Right to the STM32, there is a debugging header with GND, 3V3, SWDIO and SWCLK. Connect GND, SWDIO and SWCLK to your SWD programmer (don't connect 3V3 pin with ST-Link), like the ST-Link found on many STM devboards.
+
+In case you connected the pins and you get connection errors, make sure your ST-Link dongle pins are real, by sliding the plastic cover and checking on the ST-Link board itself. An example can be seen here https://youtu.be/XWh8yJ_p0HA?t=60.
 
 If you have never flashed your sideboard before, the MCU is probably locked. To unlock the flash, check-out the wiki page [How to Unlock MCU flash](https://github.com/EFeru/hoverboard-firmware-hack-FOC/wiki/How-to-Unlock-MCU-flash).
 
@@ -251,8 +253,14 @@ The errors reported by the board are in the form of audible beeps:
 - **1 beep fast (medium pitch)**: Low battery voltage < 35V
 - **1 beep fast (high pitch)**: Backward spinning motors
 
+Please also note that with BEEPS_BACKWARD=1 (default setting) the board also makes a beep when the motors go backwards. If running hoverserial.ino from Arduino the backward beeps are normal, unless you intentionally disable them.
+
 For a more detailed troubleshooting connect an [FTDI Serial adapter](https://s.click.aliexpress.com/e/_AqPOBr) or a [Bluetooth module](https://s.click.aliexpress.com/e/_A4gkMD) to the DEBUG_SERIAL cable (Left or Right) and monitor the output data using the [Hoverboard Web Serial Control](https://candas1.github.io/Hoverboard-Web-Serial-Control/) tool developed by [Candas](https://github.com/Candas1/).
 
+HC-05 (https://www.aliexpress.com/af/HC-06.html) works, connected to USART2 at 9600 bauds (define DEBUG_SERIAL_USART2 and USART2_BAUD=9600).
+
+In main.c you can see at [lines 440](https://github.com/EFeru/hoverboard-firmware-hack-FOC/blob/cf7b1d0de1da34612b056c316480f47702a15cbe/Src/main.c#L440) and [line 224][https://github.com/EFeru/hoverboard-firmware-hack-FOC/blob/cf7b1d0de1da34612b056c316480f47702a15cbe/Src/main.c#L225] printf statements, wrapped in ```#if defined(DEBUG_SERIAL_USART2) || defined(DEBUG_SERIAL_USART3)```. Feel free to add more printf statements with same wrapping, in main.c, in places you want to see what happens.
+
 ---
 ## Projects and Links