tBlabs / BluePill.Firmware

TODO

• remove RTC (or updates in config)
• supress leading zeros in Display (or add to config)

BluePill.Firmware

Firmware for BluePill development board.

7x Input
7x Output (including build in LED)
4x ADC
4x PWM
1x RTC
1x 4-digit 7-seg Display

Drivers

• BluePill.Driver - Standalone host with REST API
• BluePill.Client.Lib - Library for Node projects

Board pinout

                             G     3
                             N     V
                             D     3
                             | | | |
                    N/C --o  o o o o  o-- 3V3
 Output1 (build in led) --o           o-- GND
                    N/C --o           o-- 5V
                    N/C --o           o-- Input3 
                   ADC1 --o           o-- Input4
                   ADC2 --o           o-- Display Latch 
                   ADC3 --o           o-- Display Clock
                   ADC4 --o           o-- Display Data
                 Input7 --o           o-- N/C
                Output2 --o           o-- N/C  
                   PWM1 --o           o-- N/C
                   PWM2 --o           o-- Output3
                   PWM3 --o           o-- Output4  
                   PWM4 --o           o-- Rx   
                 Input1 --o           o-- Tx   
                 Input2 --o           o-- Output5  
                  RESET --o           o-- Output6
                    3V3 --o           o-- Output7  
                    GND --o           o-- Input5  
                    GND --o    USB    o-- Input6 

Peripheral connection

       GND ----- button ----- Input         <--- button pressed == value 1
       
                      ADC 
                       |
       GND ----- potentiometer ----- VCC 
       
       GND ----- unused ADC                 <--- connect unused ADC to GND
       
       uC Tx ----- Host Rx                  <--- by Host we mean PC or R-Pi
       uC Rx ----- Host Tx
       
       Output ----- led ----- GND           <--- value 0 == led on
       
       PWM ----- led ----- GND              <--- value 0 == led off

Serial config

19200:8:1:n
Tx pin: A9
Rx pin: A10

Request

0xBB 0xAA {FrameType:8} {DataSize:8} {Data:0+} {Xor:8}

Type	Value	Data size	Params	Possible response
Ping	0x01	0 bytes	none	Pong
Get	0x02	1	addr:8	Update / Error
Get all sensors	0x03	0	none	UpdateAllSensors / Error
Set	0x04	5	addr:8, value:32	Update / Error
Config read	0x05	0	none	ConfigUpdate
Config write	0x06	2	pushMode:8, scanInterval:8	ConfigUpdate
Get all	0x07	0	none	UpdateAll

Response

0xAB {FrameType:8} {Data:0+} {Xor:8}

Type	Value	Data size	Data values
Pong	0x01	0 bytes	none
Error	0x02	1	errorCode:8
Update (single IO)	0x03	5	addr:8, value:32
All sensors update	0x04	12*4	input1:32, input2:32, ..., rtc:32
Config update	0x05	2	pushMode:8, pushInterval:8
All IO update	0x06	25*4	input1:32, ..., displayDot:32

Config

Byte index	Usage	Default value
0	Push mode (0x00 - None, 0x01 - All, 0x02 - Single)	Single
1	Push interval	20 ms

Default push mode is Single with 20ms interval. That means that the only auto updated value you should see after power up is RTC (every 1 second).

IO addresses (addr param to pin mapping)

Addr	Type	Pin
0x00	Digital input	B10
0x01	Digital input	B11
0x02	Digital input	B9
0x03	Digital input	B8
0x04	Digital input	B13
0x05	Digital input	B12
0x06	Digital input	A4
0x07	ADC	A0
0x08	ADC	A1
0x09	ADC	A2
0x0A	ADC	A3
0x0B	Real time clock	None
0x0C	Digital output	C13 (build in led)
0x0D	Digital output	A5
0x0E	Digital output	A12
0x0F	Digital output	A11
0x10	Digital output	A8
0x11	Digital output	B15
0x12	Digital output	B14
0x13	PWM	A6
0x14	PWM	A7
0x15	PWM	B0
0x16	PWM	B1
0x17	Display value	B5 (data), B6 (clock), B7 (latch)
0x18	Display dot	N/D

Programming with J-Link

J-link SWD pinout

Vref --o   o-- NC
N/D  --o   o-- GND
N/D  --o   o-- GND
DIO  --o   o-- GND
CLK  --o|  o-- GND
N/D  --o|  o-- GND
SWO  --o   o-- GND
RST  --o   o-- GND
N/D  --o   o-- GND
5V   --o   o-- GND

N/D - not used
SWO - not used

STM32F103C8 SWD pins

           G C D 3
           N L I V
           D K O 3
           | | | |
Vbat --o   | | | |  o-- 3,3V
C13  --o   o o o o  o-- GND
C14  --o            o-- 5V
       |    Blue    |
      ...   Pill   ...
       | (top view) |
RST  --o            o-- B15
       |            |

Connection

J-link	Blue Pill
GND	GND
CLK	CLK
DIO	DIO
Vref	3V3
RST	RST

Blue Pill powering

STM must be powered from external 5V source.
J-Link 5V out is not working.

Chip burn

Use Visual Studio + VisualGDB

CLI?

No idea

Testing from serial terminal (Br@y++)

Ping-Pong

Set terminal Receiver into HEX mode.
Send $BB$AA$01$00$10. You should receive AB 01 AA response.

Build in led (pin C13) on/off

Send $bb$aa$04$05$0c$00$00$00$00$1c to turn LED on. $bb$aa$04$05$0c$01$00$00$00$1d to off.