STM32F103C8T6 Blue Pill project

[jw11432]

First and foremost, as of this point I know virtually nothing about these MC's but through this project, I'm hoping to learn. What I'd like to get some assistance on is just a few basic pointers and perhaps direction so that I'm not chasing my tail.

The project is to enable an instrument cluster from a slightly newer vehicle (2003) be used in a slightly older vehicle (2002). Most of the gauges will work by simply re-pinning the connector, but there are 2 gauges that require a PCM swap and tuning to get working, the volts gauge and the oil pressure gauge. As best I can tell, both the 2002 and 2003 rely on Class 2 serial data, interpreted by the PCM, to feed these 2 gauges. So I want to bypass the PCM, have this data from sensors feed into this hypothetical module I want to build, which will then correctly display the data I want to see on these 2 gauges.

I hope this clearly explains the goal and the hurdle that exists. So what I'd like some input on specifically is how best to go about setting up my environment for this. I've located a STM32 dev board (for which this post is titled) and USB to UART programmer, but I'm thinking I also need a suitable voltage regulator to ensure proper voltage is maintained for this dev board, among other things. Or if even there are some good resources for the foundations of what I'm wanting to do, I think even that would be very beneficial. I'm coming from a background of database development, so aspects of coding logic are pretty familiar, I just have no idea where to start here. Thanks!

[Peter BENSCH]

Welcome @jw11432, to the community!

First of all, you should be aware that the Blue Pill is not an ST product. They also have not contained the original STM32F103 for years, but only fakes devices. There has already been a lot of discussion about this here in the community.

What kind of device is the USB-UART programmer you mentioned?

For serious work, you should use a real board with KGD (known good device), e.g. one of the NUCLEO boards. If you only want to talk to your car (presumably via CAN), one of the small NUCLEO-32 boards may be sufficient.

As far as the voltage regulator is concerned, which source do you want to power your system from? If it is the car battery, you can simply use an LD1086V33-DG or similar linear 3.3V regulator due to the relatively low current consumption of a NUCLEO. Although the LD1086 is excessively overpowered with a maximum of 1.5A, it can be easily handled for small quantities.

Hope that helps?

Regards
/Peter

[Techn]

You have to protect the device during starting of the car. Use enough recouping for the sense of the battery voltage. Some averaging etc would be needed . Range of the output of the oil sensor should be scaled down...