Hi guys, Here is the situation I've 89c51 microcontroller board which I want to connect with PC as well as GSM but as everybody knows it(8051) has only one UART so one solution is try using 87xx or 83xx series of controller but that means I'll have to change my programmer. So what I'm thinking is I'll use simple mux/demux for Tx/Rx of 8051. I want to know will it be o.k.? Can simple AND or OR gates can handle data rate of 9600bps?
Thank you very much in advance.
If you got a controller with ISP and two UARTs you wouldn't need a programmer and you'd solve the problem!
Thank you for suggestion. I considered it however the thing is right now I never want to waste my time on learning for how to use ISP and all. I just finished my college and trying my hands on some products anyway if its not possible at all then i'll have to go for that option. I have seen 89c51re with 2 UARTs and an ISP can you direct me on how to program it? I am good at programming in C in uVision how much change will I have to do in my program etc.
"I never want to waste my time (sic) on learning for how to use ISP and all"
What makes you think that would be a waste of time?! I would rather call it a worthwhile investment - as it will save you from wasting your money on programmers and your time on stuff like multiplexing serial ports!
Have you tried a search for "multiplex" or "multiplexing"...?
Ya that sure is an investment but I wanted to get that product ready.And yes I searched a lot but couldn't find anything about multiplexed serial. O.K. now can you please guide e how to start with ISP programming frankly saying I know nothing about ISP, just its In System Programming and done via Serial port of PC thats all
now can you please guide e how to start with ISP programming
Assuming you are using the AT89C51RE2:
The chip has a built in bootloader program that operates via one of the UARTs. Details of how to invoke it and how to use it to copy your program into the internal code space are given in the datasheet and associated application notes. You will find reading these documents more useful than a question and answer session on the forum.
Thats cool Thanks a lot I'll start right away
but as everybody knows it(8051) has only one UART
It is, of course, true that "many '51 derivatives have only one UART", however it is equally true tha many modern '51 derivatives have 2 UARTS.
Erik
Ya that sure is an investment but I wanted to get that product ready.
It has to be pointed out that you're contradicting yourself there. You have to decide what the goal is going to be: getting the product ready, or learning stuff on your own free time. The approach to steps like picking a controller has to be different in each case.