Microcontroller STM8S003F3 - LED display driver

[reverbus]

Hi people!
As it is my first post here, greetings to all members.

First of all I couldn't find any results via search function, regarding my question.

I bought cheap and small Led display 0-99.9V:
**broken link removed**

Panel is driven by microcontroller STM 8S003F3 P6 (TSSOP).
https://www.electro-tech-online.com/custompdfs/2012/10/DM00024550.pdf

I'd like to have 0-9.99V meter, so I have to move decimal point.
There are two resistors as voltage divider on input, I can set this combination for needed range.
But, how to move decimal point?
I don't see (think) some rewiring would help, ...is it done inside software?
It is obviously I'm not domestic with microcontrollers, so if anybody know how to do this, let me know please.

Regards

 

[panic mode]

is there a datasheet

 

[DirtyLude]

It's a microcontroller and not a dedicated LED Display Driver. If you want the functionality to change you will need to reprogram it.

You'll need to reference that datasheet for the STM8S.
You need to determine if the programming lines run out to contacts on the board to make it easy to reprogram. There are two pictures of the back on that page and both are different, but it looks like there might be an unpopulated header for in circuit programming/debugging.

I have not used the STM8 line, so don't take any of this as gospel, but you will need a programmer to program it. The STM8S-Discovery board comes with a ST-Link programmer that will program/debug this chip. Search for STM8S-Discovery and you can buy this pretty cheap.
You then need to actually program it. The code in the chip is likely protected and having the binary isn't going to help you much anyway. In fact if you haven't done any coding before, there is a steep learning curve here for you. You will need to write a program to read the analog input, convert it and then display it on the 7 segment display.

There are definitely people here that have tried out the STM8s line that could give you better detail, but that's generally what you are up against.

Wow. $25 is a huge markup on this thing.

 

[dougy83]

I'd like to have 0-9.99V meter, so I have to move decimal point.
There are two resistors as voltage divider on input, I can set this combination for needed range.
But, how to move decimal point?

There's 11 pins (digits are multiplexed), so that's likely to mean the DP is driven as if it were another segment of the display. This means that it's not possible to reroute any traces to change the DP.

If you want to program the thing you can probably use the 4-pin connector which I assume is for SWIM (programming port). You'll probably have to rewrite the whole program, which is not hard for someone experienced, but more difficult otherwise. It's very easy to get the compiler set up and running. I assume the programmer/debugger is just as simple to use.

Wow. $25 is a huge markup on this thing.

It's $2.50/piece including postage.

 

[DirtyLude]

It's $2.50/piece including postage.

I see, it's for quantity 10. I thought the price was pretty crazy.

 

[dougy83]

I see, it's for quantity 10. I thought the price was pretty crazy.

I reckon $2.50 is pretty crazy - how do they make any money on that?

Here's one for $2, and it comes with a bezel. Looks like a similar circuit too
**broken link removed**

 

[reverbus]

Thank you guys for promprt and extended explanation!
I see I'll have to add digital/mc knowledge to my library

I think I'll order those one already programed for my needs as I have to finish a project.

Regards