[EN] TMA‐1 DIY Guide
Monolith is a DIY datalogger project where each user needs to build their own hardware.
This guide explains how to build the hardware and upload the firmware of the TMA-1 datalogger.
The PCB of the TMA-1 is designed with the KiCAD 7.0 and is a key component to build your hardware.
If you want to use the modified PCB of your own, you can download the circuit diagram and PCB artwork at device/hardware.
Download the PCB gerber file and order the sample PCB.
These sites support online order placement by uploading the gerber file. Just choose your PCB color and order it.
The prototype of the Monolith TMA-1 was sponsored by PCBWay.
TMA-1 can activate each feature individually to reduce the build cost.
Each area of the feature is marked on the PCB. (TELEMETRY, CAN, DIGITAL, ANALOG, PULSE, ACCELEROMETER, GPS)
For not using features, you don't need to install the components on the PCB. You can just disable the feature in the TMA-1 Configuration Tool.
The predefined resistance values are marked on the footprint of each resistor. If there is no value on the footprint, it means that you should calculate your proper resistance.
These resistors that need your calculations are only on the ANALOG section(R25-R32) and the PULSE section(R35, R36).
This is a list of components that need to be installed on the PCB.
- Marked quantity is the minimal quantity for the build.
- Marked price is the approximate value at the point of this guide was written.
I'm from South Korea and have no idea which sites other countries are using to purchase electronic components. I found out that some modules popular in our country are not popular in other countries.
Hence, I attached the exact product links from eBay and Aliexpress. Popular components such as resistors, capacitors and comparators(LM393) are not linked.
It costs approximately $75 to build one TMA-1 in South Korea. I have no idea about other countries.
This is a list of essential components to run the TMA-1.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| PCB | - | 1 | JLCPCB ($18) | Price of 5 PCBs, which is MOQ. |
| STM32F407VET6 DEV board | U1 | 1 |
eBay ($19.87) Aliexpress ($9.99) |
If you have coins, you can purchase the Aliexpress one at about $8.2! (This is a coin shop link. You can take 18% additional discount when you click "Buy Now", instead of adding it to the cart.) |
| 2*40 2.54mm pin header socket | U1 | 2 | eBay ($3.42) | This is for install STM32 dev board on the PCB without soldering. Actually it needs 2*24 pins only, so cut it to fit the dev board. |
| MP1584EN 3.3V DC-DC converter | U3 | 1 |
eBay 1 ($9.99 / 10) eBay 2 ($3.53) Aliexpress 1 ($1.5) Aliexpress 2 ($3.55 / 5) |
There are two types of the converter: adjustable and fixed output voltage. We need 3.3V output. So, please purchase 3.3V fixed type or set the adjustable type to output 3.3V using DMM. |
| MOLEX 5569-24A Main I/O connector | J1 | 1 | You can use 5566-24A too. | |
| MOLEX 5557-24R Main I/O connector plug | 1 | |||
| MOLEX 5557-24R Main I/O connector plug terminal | 30 | |||
| 5mm LED | D1-D6 | 6 | - | Choose the color at your preference. |
| 1/4W LED series resistors | R1-R6 | 6 | - | Supply voltage of D1-D6 LEDs is 3.3V. Choose the proper resistance per LED color. LED Series Resistor Calculator Approximately 100 ~ 330Ω will fit. |
| 1/4W power voltage measure resistors 9.1kΩ, 1.3kΩ |
R23, R24 | 2 | - | These are 1/8 voltage dividers to measure the LV voltage. One 9.1k and one 1.3k resistor is needed. |
| 1*3 2.54mm pin header | J2 | 1 | This is a UART header for DEBUG output. | |
| STLink v2 | 1 |
eBay ($3.85) Aliexpress ($2.19) |
This is a hardware debugger used to upload the firmware to the TMA-1. | |
| UART to USB converter | 1 |
eBay $(2.25) Aliexpress ($2.35) |
This is used for reading DEBUG UART output and synchronizing RTC of the TMA-1. |
Refer to the image of the TMA-1 at the top of the guide and install MP1584EN 3.3V converter in the proper direction.
STM32 Dev board should be installed in the direction of the SD card slot heads top.
This is a list of components to activate the telemetry feature.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| NodeMCU-32S ESP32 Dev Board | U2 | 1 |
eBay ($5.32) Aliexpress ($4.3) |
Choose Type C in eBay and ESP32 CP2102 TYPE-C option in Aliexpress.This is a product without mounting holes at the corner of the PCB. Watch out the similar products like ESP32-devkit. |
| 1/4W 2.7kΩ I2C pull-up resistors | R41, R42 | 2 | - | |
| 1*40 2.54mm pin header socket | U2 | 1~2 | This is for install ESP32 dev board on the PCB without soldering. Dev board has 38 pins, so you can cut one socket into 2 pieces. |
|
| EN 10uF capacitor | C1 | - | - | This is a capacitor for ESP32 firmware upload without pressing EN button. |
ESP32 Dev board must be installed in the direction of the USB port heads upward. Also, watch out for the polarity of the C1 cap.
This is a list of components to activate the CAN bus traffic monitoring.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| SN65HVD230 CAN Transceiver Module | U8 | 1 |
eBay ($2.71 / 2) Aliexpress ($1.86) |
Module must be installed in the direction of IC to face downward of the PCB. Please be aware of the pre-installed 120Ω termination resistor. If there are already all termination resistors present on the bus, you must remove the module's one. |
| CAN bus toggle switch | SW1 | 1개 |
eBay ($5.7 / 3) Aliexpress ($31.4 / 100) |
This is a toggle switch to detach the TMA-1 from the CAN bus. This is a small version of MTS-202, which is SMTS-202. If you don't need this, short the middle and bottom pins of each column to skip it. |
The product image of TMA-1 has a CAN transceiver with the wrong silkscreen printed. Ignore the silkscreen text of the transceiver and focus on the chip direction.
This is a list of components to activate the 8-channel digital signal monitoring.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| 2N3904 general purpose NPN TR | Q1-Q8 | 8 | This is a Wide TO-92 footprint which has 2.54mm pin pitch, instead of 1.27mm of TO-92. | |
| 1/4W 1kΩ current-limit and pull-up resistors | R7-R22 | 16 | - |
This is a list of components to activate the 4-channel analog signal monitoring.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| 1/4W voltage divide resistors | R25-R32 | 8 | - | Calculate your own resistor values. |
Maximum input voltage of the STM32's ADC is 3.3V. Set the proper resistance to divide the input signal voltage level.
If you are using 5V analog signal, set 470Ω on the odd number marked resistors and 910Ω on the even number marked resistors.
If you are using somewhat else voltage, set the divide resistors that makes max voltage to 3.3V.
You can decide it by Max input voltage * (even number resistor value) / (odd number resistor value + even number resistor value) = 3.3.
This is a list of components to activate the 4-channel wheel speed sensor(digital pulse period) monitoring.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| LM393P/N Comparator(DIP-8) | U4, U5 | 2 | Note that this component has a 8-pin through-hole(DIP-8) footprint. | |
| 1/4W reference voltage divide resistors | R35, R36 | 2 | - | This resistors set the reference voltage to LM393 comparator's - pole. Calculate your own values refers to your sensor's reference voltage. |
| 1/4W 1kΩ pull-up resistors | R33-R38 | 4 | - |
This is a comparator circuit that can make various voltage pulse signals to 0V / 3.3V for STM32.
The reference voltage for LM393 that distinguishes the HIGH / LOW is set by R35 and R36.
If you want to set the reference voltage to 1V~1.1V, set R35 to 680Ω and R36 to 330Ω.
If you want to decide your own, use reference voltage = 3.3 * R36 / (R35 + R36).
This is a list of components to activate the ADXL345 3-axis acceleration monitoring.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| ADXL345 accelerometer module | U6 | 1개 |
eBay ($1.99) Aliexpress ($1.5) |
This is a long, both-sided 10 pins module. Watch out not to confused with the GY-291, which as one-sided 6-8 pins. |
| 1/4W 2.7kΩ I2C pull-up resistors | R39, R40 | 2 | - |
Install the accelerometer in the direction that the pin name silkscreens on the PCB match with the sensor's silkscreens.
This is a list of components to activate the NEO-6/7M GPS monitoring.
| Component | PCB marking | Quantity | Product link | Notes |
|---|---|---|---|---|
| NEO-6M/7M GPS Module | U7 | 1개 |
eBay ($3.41) Aliexpress ($2.05) |
Both NEO-6M and NEO-7M are ok. But you cannot use products that have antenna attached below the module. The stock antenna provided with the module will not be used. |
| SMA to UMCC cable | - | 1개 | Adafruit ($3.95) | This is a cable to use standard GPS/GNSS antennas instead of the stock NEO-6/7M antennas. |
| external GPS antenna | - | 1개 | eBay ($3.44) | This is a replacement of stock NEO-6/7M antenna. You can use any GPS/GNSS antenna with SMA male connector. |
If you finished building the hardware, the next step is uploading firmware to your TMA-1.
You can refer to the TMA‐1 Configuration Tool Guide to build and upload the firmware to the TMA-1.