Programming

Here you will find the details needed for develop your own firmware for the device

If you are interested in writing firmware for the VALTRACK-V4-VTS device, you will need to know where is each pin of MCU is connected to.

Since the schematics of the device is not yet openly available, We are providing the MCU pin connection details, which should be able to help you in determining how is the whole architecture laid out. Watching our device intro video would also help to get an overall idea on the hardware present on board.

MCU Pinout Details

Pin Number

Pin Name

Net Name

Connected to

2, 3, 11, 17, 18, 31, 32

VDD3P3, VDD3P3_RTC, VDD3P3_CPU, VDD_SPI, VDDA

3V3DC

3.3VDC output of LDO

19, 20, 21, 22, 23, 24

SPIHD, SPIWP, SPICS0, SPICLK, SPID, SPIQ

CLK_IN

32.768 KHz crystal

1

LNA_IN

RF_ANTENNA

Bluetooth / WiFi Chip antenna via matching network

4

GPIO0

LPUART1_TX

Cellular module RXD input pin through level translator.

5

GPIO1

LPUART1_RX

Cellular module TXD output pin through level translator.

6

GPIO2

ANALOG_IN

VCHG input through voltage divider resistor network.

  • R22,R33 govern the voltage at this pin.

  • Default values : R22 = 100K, R33 = 3.3K

7

CHIP_PU

CHIP_PU

CHIP_PU line

9

GPIO4

TPS_ENABLE

Enable input of switching regulator TPS54240

  • Making this pin high powers the system via VCHG connector.

This will cause system into reset loop if no alternate backup battery power available Do no activate this pin without connecting a 3,7V battery to avoid Race around condition

10

GPIO5

IIC_DATA

I2C data of LIS3DH Accelerometer

12

GPIO6

IIC_CLK

I2C clock of LIS3DH Accelerometer

13

GPIO7

SIM_PWRKEY_3V3

Cellular module PWRKEY pin through N channel MOSFET.

  • Making this pin HIGH pulls PWRKEY pin to GND

14

GPIO8

LED_SIGNAL

WS2812B battery LED input

15

GPIO9

GPIO9

Tactile switch input

  • Pulled up, filtered and Active LOW

16

GPIO10

GSM_ENABLE

Enable input of power gating MOSFET for Cellular module

  • Making this pin high provides ~4VDC to Cellular module

25

GPIO18

USB_DN

USB DP line

27

GPIO20

U0RXD

Drawn to test points

28

GPIO21

U0TXD

Drawn to test points

29

XTAL_N

OSC_OUT

40 MHz crystal

30

XTAL_P

OSC_IN

40 MHz crystal

26

GPIO19

USB_DP

USB DN line

33

GND

GND POWER PAD

GND

J62 - VCHG Connector [SMT pads] - Pinout Details

Pin Number

Pin Name

Connected to

1

VCHG

VCHG input of system through FUSE and diode

  • 12VDC to 42VDC input

2

GND

System Ground

J41 - VBAT Connector [SMT pads] - Pinout Details

Pin Number

Pin Name

Connected to

1

VBAT

VBAT input of system or Backup battery input

  • 3.7V to 4.2V battery input

2

GND

System Ground

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