Hardware

Summary

• 128x32 SSD1306 OLED - SPI2 SCK 6 MOSI 5 RST 4 DC 28 CS 29
• PAH8001 HR sensor - TWI0 SCL 7 SDA 8 speed 400kbps, enable pin 26, I2C address 0x6b
• KX022(?) accelerometer - TWI1 scl 13 sda 14 speed 400kbps, I2C adress 0x1f
• USB plug data pins 22,23 - configured in DFU bootloader as UART RX(22) TX(23) baud rate 38400
• motor - pin 25
• touch button - pin 30, goes low when touched
• charging power detect - pin 2

Firmware source code strings

strings dsd6-flash.bin | grep -i '\.c' | sort | uniq

..\components\ble\device_manager\device_manager_peripheral.c
..\components\libraries\simple_timer\app_simple_timer.c
..\components\libraries\timer\app_timer.c
..\components\softdevice\common\softdevice_handler\softdevice_handler.c
..\source\HeartRate\HeartRate_PAH8001.c
..\source\src\ds_clock.c
..\source\src\ds_hisdata.c
..\source\src\ds_hisdata.c
..\source\src\ds_power.c
..\source\src\ds_spi_master.c
..\source\src\ds_spi_master.c
..\source\src\ds_wdt.c
..\source\src\gclock.c
..\source\src\i2cdriver.c
..\source\src\KeyEventHandler.c
..\source\src\KeyEventHandler.c
..\source\src\kx_gsensor.c
..\source\src\main.c
..\source\src\main.c
..\source\src\MainUI.c
..\source\src\MainUI.c
..\source\src\MotorEventHandler.c
..\source\src\uartdriver.c

• PAH8001 HR sensor
• KX gsensor
• i2c driver - gsensor and hr sensor?
• spi driver - OLED?
• uart - hopefully on USB data pins?

Register dumps

Register dumps made over SWD when rebooted to DFU bootloader (serial enabled!) and later also app (no serial but i2c enabled)

UART https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/uart.html?cp=2_1_0_49_9#topic

0x40002500:	0x00000004	0x00000000	0xffffffff	0x00000017
0x40002510:	0xffffffff	0x00000016	0x00000000	0x00000000
0x40002524:	0x009d5000

rx 0x16 22
tx 0x17 23
no parity
baudrate 38400

SPI https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/spi.html?cp=2_1_0_47_1#topic

0x40023500:	0x00000001
0x4002350c:	0x00000006
0x40023508:	0x00000005
0x40023510:	0xffffffff
0x40023524:	0x80000000
0x40023554:	0x00000000
spi2 master sck 5 mosi 6 miso -1 speed 8mbps config msb,sample leading shift trailing,acthigh

TWI https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/twi.html?cp=2_1_0_48_7#topic

0x40004500:	0x00000005 = ENABLED TWI
0x40004508:	0x0000000d = PSELSCL 13 
0x4000450c:	0x0000000e = PSELSDA 14
0x40004524:	0x06680000 = FREQUENCY 400kbps
TWI1 scl 13 sda 14  speed 400kbps

0x40003500:	0x00000005
0x40003508:	0x00000007
0x4000450c:	0x00000008
0x40003524:	0x06680000
TWI0 scl 7 sda 8 speed 400kbps

GPIO https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/gpio.html?cp=2_1_0_19_2#topic

0x50000514:	0x36000070 DIR
0x50000504:	0x00006190 OUT
0x50000510:	0x41216040 IN no charging
0x50000510:	0x40216044 IN charging
0x50000510:	0x40e16004 IN display on
after using also hr sensor
0x50000504:	0x34806190 00110100100000000110000110010000 OUT
0x50000510:	0x40e17984 01000000111000010111100110000100 IN (charging, display off)
0x50000514:	0x36800070 00110110100000000000000001110000 DIR (1=output,0=input)

inputs:
pin 2 goes high when power is attached to usb
pin 30 touch button, goes low when touched
outputs:
pin 4 when display is on and set to 0 display goes off (RST?)
pin 25 motor
pin 26 enable HR sensor
pin 28 ?
pin 29 ?