CRAFTSMANBLE

CraftsMan BLE is designed to send accelerometer&Gyroscope data over BLE and serial port toany BLE Client and/or computer with a serial port.

Systems requirements:

1. M5 Stick-C Plus (the device that will send the data) as BLE Server
2. BLE Client a Mobile phone using Bluefruit LE Connect on iOS or Android
3. and a Laptop with Arduino IDE

Installation

1. Download the CraftsmanBLE.ino file to your Arduino sketches directory
2. Compile it (Make necessary changes in case you are using a M5-Stick instead of a M5 Stick C plus. Note the only changes needed with be the Button numbers for Button A,B, IMU initialisation and IMU read commands, and the LCD print commands.

Usage

1. Reset the M5-StickC plus

2. Connect Mobile to "Kosha Craftsman" servie using the BLE software

3. Hit Connect

4. Click UART under modules section

5. On the M5-StickC Plus - Click Button A to start reading IMU readings

6. After a few seconds click Button A to stop the accelerometer readings.

7. M5 Screen will show the number of readings taken(see last line)

8. Click button B - to dump the readings in CSV format to BLE Client device

9. Click "Settings" icon, Export, Copy as txt.

10. Long Press A to restart device.

Version 2.0 Usage instructions

Version 2.0 allows control of M5 from the BLE Client device as follows

• All commands are single letter command (case insensitive)
• An optional integer (max 3 digits) follows the command

S.No	Commands	Argument	Remarks
1	S	None	Start reading IMU
2	S	None	Stop reading IMU
3	D	None	Dump readinds to BLE Server
4	R	None	Restart M5
5	P	nnn	Set period to nnn millisecs
6	O	nnn	Set offset to nnn millisecs

introduced a way to control M5 from the mobile phone

Libraries used

1. M5 Stick C plus
2. ESP32 Arduino BLE
3. Easybutton

Other info:

1. CraftsmanBLE is set to take readings every 100 ms. you can change that by changing delta_T
2. The current buffer size can accomodate a max of 3000 accelerometer readings, if the number of readings exceed 3000 then the buffer pointer will fold back to 0 and start writing from top of buffer. Acts like a ring buffer.
3. Sorting the data on seqno will provide you the right order of readings even if the buffer has folded.
4. a 10ms delay is inserted while writing to BLE client- this is ensure BLE server is not overwhelmed.

Version History

• 1.0 :17/Feb/21 Output consisted of 3-axis Accelerometer readings
• 1.1 :19/Feb/21 Output now includes 3-axis Accelerometer and Gyro readings
• 1.2 : 1.5 :23/Feb/21

1. SeqNo in BLE output is replaced by secs.999 (starts at 0.000) 
2. The interval time is very close to desired delta_T using delta_offset
3. Long Press A button till beep to restart device
4. If connected to physical serial port you can still read old seqNo along with Secs 
5. Device has a unique name derived for chip id and prefixed by KoshaCraftsman

• 2.0 :03/Mar/21
  • Use Serial Input to provide commands to change Period and Offset

1. Single letter command followed by a max 3 digit number
2. example P100 or p100 will set period to 100ms
3. example O20 or o20 will set offset to 20ms (DONT USE THIS FOR NOW)
4. note: Period has to be greater than processing time ie delta_offset
5.       Offset cannot be very large betwee 24 and 30 ms
6. program will ignore values outside this range.
7. s or S to start/stop reading activity
8. r or R to restart M5