Hi everybody.
I'm a new person in forum,my English not good.I have a project is "Control device in home via PC",and programming with VB6.
anyone have schematic circuit interface 89C51 with serial port,please send to me,thanks a lot
my email is:ngocky@qtsc.com.vn
thanks and regards
To connect 8051-derivative to a PC computer via serial port you don't need much ..
Any TTL/CMOS-to-RS-232 interface IC will do ..
Try configuration shown below ..
Easiest solution ever. Use MAX232 from www.maxim-ic.com, download the datasheet for h/w connection. Use Timer0 or Timer1 as a baudrate generator (You can find here a good 8051 baudrate calculator www.8051.com) and start talking to your uC serially.
hi..
its a word document frend.. just open it i v pasted the object there. this is the circuit we are using for years.. and we hav successful serial communication.
hey ngocky
if ur final aim is to control devices through d pc then d microcontroller is not necessary........it wud be much simpler if u used just d parallel port programmed through vb or c
You can use USB, but as this is a message based protocol, it can be quite slow. Using a true RS232 port on your PC is better, if your PC still has one.
To convert the RS232 signal levels to TTL, the best chip to use is an ICL3221. This is affordable and works with a power supply voltage between 3 and 5 V.
You can build your own or buy a ready made one here **broken link removed**. This page also includes a full schematic and the datasheet of the ICL3221.
Hi
can you people give give some program(code) for serial com. with micro controller 89s51, i m testing weather my serial communication working properly or not .