When you need connect your Microcontroller Project to COM port in PC you need RS 232 converter. There are many chip to solve the problem like MAX232, DS275 etc. But if you need simple and chep for RS 232 converter, i though this circuit will be usefull for you. The design made by Wichit Sirichote.
"A circuit diagram shown above was used two small signal transistor, NPN and PNP transistors. Dash line separate transmitter and receiver circuit. For those who need only transmitter circuit can use above circuit (and GND (5) signal ). Technically the RS232C is -3V to -12V for logic '1' and +3V to +12V for logic '0'. The transmitter circuit uses PNP transistor, BC557. While in mark state the TxD signal is logic '1', Q1 turns off. TxD (pin3) then provides -9V (depends on what converter chip being used for COM1, say) to RxD (pin2). For space state, TxD control signal then becomes logic '0', which turns on Q1, the approx. +5V is then fed to RxD (pin2). With this method, while sending data has being made, TxD (pin3) must stable at -9V, say"
There also some modification from above circuit. For more detail you can download here.
link
Free Magazines
Download this guide to learn and understanding everything you need to know about the Raspberry Pi computer, system specs, the software it runs and the amazing project based on this little PC.
PEI is the leading magazine for the global electric power generation and transmission industry. PEI provides articles on new technologies and installations and analysis.
Subscribe Fof Free!
EDN magazine provides how-to solutions for design engineers in the electronics industry. Engineers turn to EDN because they know they will always find valuable design techniques that they can use to do their jobs faster.
Subscribe Fof Free!
More Free Engineering Magazine
Headlines
0 Comentar:
Post a Comment