• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Microcontroller selection help

Not open for further replies.


New Member
Hi there,
I am a University student in Australia and am currently trying to find a microcontroller to suit this application.

I have two serial devices one a mobile phone that requires 9600 baud that will need to receive and send data to and from the uC. The other device is a GPS receiver that sends characters to the uC at 4800 baud.

I guess my first question is there any ideas on a low cost uC that would do the job?

I was also wondering how in the software I could store the bytes as messages from the phone could be as long as 25+ bytes I have done some uC programming of the serial port however it was only sending of data not receiving. Can anyone point me in the direction of where to start in this area?

Thanks Heaps,


Active Member
8051 Microcontroller with multiplexed serial port can do your job and its very cheap.

Do these both communications happen simultaneously? If yes then multiplexing won't work. If not, let me know I'll post the schematic of port multiplexer.


New Member
No they don't need to happen at the same time
If you could post the schematic that would be great



Active Member
Ok here is the schematic. Remember, both ICs are 74HC type. One has been shown LS by mistake.

The microcontrollers I would like to suggest you are:
AT89S52 (8kB Flash ROM)
AT89S53 (12kB Flash ROM)

Both these are very easy to program and they are In-System Programmable. So debugging your program will be very easy.



Well-Known Member
Define 'low cost'.
What other requirements are here? Are you studying to actually use microcontrollers, because I've been burned by this before. If you are studying for a profession where using a microcontroller is helpful or advanced use is required, your answer is different than if you just need to get this one simple project done and you're actually an artist or something.

If you just need to get this done and don't actually care about learning about microcontrollers than I would vote a cheaper Arduino spinoffs.
If you want to learn something that will be used later I would use a microcontroller that has a high amount of hobby support. At this time that would be PIC or AVR, or possibly MSP430 since they have hit the hobby market hard. This is a very simple task your asking and finding a microcontroller with dual UARTs is not that difficult.


Well-Known Member
Most Helpful Member
As this thread is 10 years old, I would guess that the OP has now left university.

Not open for further replies.

Latest threads

EE World Online Articles