Need to choose simple microcontroller

[kabild2]

Hello, I am designing a rf circuit. It will be my first circuit and i have some switches on it, they need to be digitally controlled. For this purpose I have to choose a microcontroller. I thought that i will get an eval board something like stm32f4 discovery.
I am gonna need
8 x (2 pins which requires * 1 = +2.9 V to +5 V, 0 = 0 V + 0.2 V * )
2 x (3 pins Low 0 to +0.8 Vdc at 0 µA Typical
High +2.0 to +5 Vdc at 20 µA Typical
and 1 pin for Vdd +5V typical, 4mA typical)

So at total i need 8x2+2x4=24pins which needs to be controlled.

I have used for a small period of time that eval board i mentioned, but I have almost no information.

1- Is that board is enough for me ?
2- Will I use the only the GPIO pins for this purpose?, can I use all the GPIO pins?
3- Manual of this board is 1800 pages, I only need to control switches, How detailed should I work?

 

[KlausST]

Hi,

we don´t know how complex your software will be nor do we know about timing requirements.

Without knowing more details I recommend to use some arduino board with a simple 8 bit microcontroller.
Maybe it´s better to choose an even less complex controller and control the I/Os via 74HC595 shift register.

Klaus

 

[kabild2]

I at least need 24 pins to control my circuit, timing will not be an issue probably.
I want to control which switches work via PC also, So I think I use UART for this purpose? I dont have much knowledge, any help is appreciated and thank you for your response.

 

[KlausST]

Hi,

I at least need 24 pins to control my circuit,

You are free to use 3 pieces of 74HC595 daisy chained to get 24 outputs.

I want to control which switches work via PC also, So I think I use UART for this purpose? I dont have much knowledge, any help is appreciated and thank you for your response.

Choose whatever you like. Technically there is not much difference in effort. WiFi to UART module, USB to UART module, Bluetooth to UART module; RS232 to UART module...everything is available.

But it seems you didn´t do much research on your own until now.
Please do this.
Find many many similar examples. with hardware and software examples.
Find out what´s suits you best.
Modify it for your needs.

Klaus

 

[kabild2]

Thank you so much for your responses.
Can you recommend me anything for finding such examples also please?

 

[KlausST]

Hi,

https://lmgtfy.com/?q=microcontroller+HC595+circuit

Do similar with other topics you want to know...

Klaus

 

[kripacharya]

..I am gonna need
8 x (2 pins which requires * 1 = +2.9 V to +5 V, 0 = 0 V + 0.2 V * )
2 x (3 pins Low 0 to +0.8 Vdc at 0 µA Typical
High +2.0 to +5 Vdc at 20 µA Typical
and 1 pin for Vdd +5V typical, 4mA typical)....

I personally found the Atmel (now Microchip) Atmega328 Pro Mini very easy to use and with reasonable features. Quite cheap ~ $2-3 in retail, which has onboard regulator, 16Mhz resonator etc already installed. It has 23 usable I/O pins, which is exact what you need, if you discount the 1 pin for Vdd +5v.

Naturally you will need the development environment for this.

 

[kripacharya]

I at least need 24 pins to control my circuit, timing will not be an issue probably.
I want to control which switches work via PC also, So I think I use UART for this purpose? I dont have much knowledge, any help is appreciated and thank you for your response.

You can connect the Atmega328 board to PC UART. However this will take away 2 pins from the Atmega board (Tx, Rx), plus require appropriate software on the Atmega to manage the UART. Since this is a built-in feature of the chip, it is quite easy. Alternatively you can use a chip with more I/O like Atmega16 which has lesser SRAM and flash-memory (for software) but has more I/O pins available. However I do not know of any ready built boards for this.

Alternatively you can go for the Atmega32 boards (like... ?) which have plenty of everything, and are almost as cheap.

 

[kabild2]

Yes, after reading your comment, I made a quick search and found out exactly what you said.
Currently I am only considering the pin numbers and that it has to have UART pins, I dont exactly know anything else. Not sure what is SRAM is for.
For now I was thinking that I should select a good board and include it in my pcb, then while I am waiting for my pcb to come, I could learn about microcontroller part. But I think it is not that simple.

For now I have something like this on my mind; I need something where I can create a simple interface with simple coding, where I will be getting data from somewhere else, and when the data comes I will give command to my microcontroller and do the switching and do the operations, when it is completed I Will get data from somewhere else again and it will continue. I want to be able to show the status on the PC with that interface.
I dont care about price much, it can go up to 30-40$

Can you give me any idea about that. Where should i do the coding and what board do i need?

Thank you so so much for your kindness and being helpful.
Best regards..