Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Test bit-banging at the receiver

Status
Not open for further replies.

Maverickmax

Advanced Member level 1
Joined
Dec 6, 2004
Messages
404
Helped
8
Reputation
16
Reaction score
3
Trophy points
1,298
Activity points
3,689
Hello

Do you know what is the best way of testing my bit-banging at the receiver?

Because I am sure if it work properly or not.

What about software or equipment that allows me to probe the TX and RX in order to see the waveform?

By the way, is it possible to connect two microcontroller chips via RS-232?

Maverick Max
 

yes,
it's possible to connect two microcontroller chips via RS-232.that can be done without rs232 also if they have common power supply and if not u can use max232 chip to do this job.before i tell u something else tell me which uC u plan to use ?
 

Maverickmax,

Its becoming a habit :)

When I wanted to test out my MIDI controller (basically a UART) I used 'hyperterimal'
once set to the correct baud, its doesn't show you the wave form, but it does display what the packet is in ASCII. After all, it was designed for text. There are some progs on the net (free ones) that are similar but display HEX and binary, and sometimes decimal.

Also, search the board for 'soundcard oscilloscope'. Its a free bit of software that displays signals you put into the 'line in' on your sound card. All you need is a voltage divider 5:1 to get 5v to 1v. Since Line in is generally 1v p-p.

However, all this is for showing what is sent from the TX to the Rx. Whether the Rx does what it is designed to do, is down to the micro's output.

You could also use software (hyperterminal) to send data to the Rx. Send a character, ASCII, and get your bit banging micro to simply display the byte on 8 LED's. There are plenty of ASCII -> binary tables on the internet, so you can check if its working. Just get the baud right.

Btw.: For Tx -> PC(hyperterm) you probably won't need any interface circuit, just an inverter. A PC's serial port picks up on 0-5V nicely. But from PC to Rx, its using RS232 levels. So you'll need to find a way to get 0-5v. As garg29, to get true RS232 levels, you'll need the MAX232.

Good luck.
 

Buriedcode said:
Maverickmax,

Its becoming a habit :)

When I wanted to test out my MIDI controller (basically a UART) I used 'hyperterimal'
once set to the correct baud, its doesn't show you the wave form, but it does display what the packet is in ASCII. After all, it was designed for text. There are some progs on the net (free ones) that are similar but display HEX and binary, and sometimes decimal.

Also, search the board for 'soundcard oscilloscope'. Its a free bit of software that displays signals you put into the 'line in' on your sound card. All you need is a voltage divider 5:1 to get 5v to 1v. Since Line in is generally 1v p-p.

Hello again

Do you know what kind of equipment that need to plug in my sound card for measuring the incoming signal

Maverick Max
:D
 

hi,

try http://polly.phys.msu.su/~zeld/oscill.html

Its pretty basic, and obviously, because its only designed for audio, has 20Khz bandwidth. Which is fine for your app. (baud max = 20K)

As for hardware.
All you need is a voltage divider 5:1 to get 5v to 1v. Since Line in is generally 1v p-p.

Then that goes into you soundcards line in. I think either channel will work, left or right. So its 2 resistors (47K and 10K) and a 3.5mm stereo jack.

use this to check that the levels are ok, and that it has a start and stop bit.
Remeber, this only tests the output of your transmitter, not your receiver.

I would still use hyper terminal, because its difficult to see what you are sending on a scope, byte-wise. It just displays a waveform.

If you're after 'code', I'm afraid the only one I could find for your type of micro was written in assembly. I suppse you should be able to include it in your main program, without converting it to C.

**broken link removed**
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top