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EB039 USB232 issue

Posted: Fri Jan 25, 2013 7:26 pm
by B4rzan
Hi all,

I have a complete Matrix Multimedia Development System. I recently tried the USB232 eblock and I downloaded the test file on you're site. It seems to be working but I am seeing random characters on my pc!

When you send the EB039 hex file, it says please press A0 to continue. When I press A0, the following random characters are shown on my terminal window (please see the screenshot)! these characters to show in that format, is it a normal thing or have I got problem with connections.

p.s. I am using pic16f877a. Jumpers are left as default (j3=C and j4=1)
Image

Re: EB039 USB232 issue

Posted: Fri Jan 25, 2013 10:48 pm
by dazz
Hi
Can you follow the link in my sig and sign up to the relevant forum , and post your flowchart , as this will allow others to check theres not a mistake in the flowchart and also will get you a prompter responce

Regards
Dazz

Re: EB039 USB232 issue

Posted: Fri Jan 25, 2013 11:08 pm
by kersing
Have you set the clock switches correctly (XTAL and FAST)? And is the default crystal fitted onto the EB006?

Re: EB039 USB232 issue

Posted: Fri Jan 25, 2013 11:14 pm
by B4rzan
Yes I have set my clock to xtal and fast on the eb006 board. I am not using flow code am just using the test program made by mm to test the USB232 board.

Re: EB039 USB232 issue

Posted: Sat Jan 26, 2013 10:15 am
by kersing
In my experience with serial connections (and the connection between the 16f877a and the EB039 is a serial one) unreadable data is usually caused by components using mismatched speed settings.

If you run the test a couple of times do you receive the same data or do you get random data? Could you set the 'Data Format' to HEX to see if any non-printable characters are received?

Re: EB039 USB232 issue

Posted: Sat Jan 26, 2013 7:10 pm
by B4rzan
Thank you very much "Kersing", the problem was indeed the speed of the clock. to be fair it was stated in the test routine document that the system should be running on 19.6608MHz. I replaced the clock from 8MHz to 20MHz, problem solved. thanks