Service Forum

wpsx · Nou Venit Joined: 04 Nov 2022 Posts: 3

Hello I created a circuit based on this site.
https://web.archive.org/web/20070312154157/http://www.rkawakami.net:80/ibm_600x/max232_if/

but When I ran itester, SDA in remained 0, SDA out and CTL went back and forth between 0 and 1 every 5 seconds. when invert selected, SDA in remined 1 and SDA out,CTL show same results.
It is circuit picture.
https://flic.kr/p/2nXeWx7

Are there any different parts of the circuit?　　
Also, the serial port part is a kit soldered for breadboard.[/b]

victor · S.F. Boss Joined: 07 Mar 2004 Posts: 2546 Location: Staff

Hi,

The diodes look to be switched. So invert them, the cathode (black strip) should be towards the IC.
_________________
Victor Voinea
ALLservice HQ, Romania.

wpsx · Nou Venit Joined: 04 Nov 2022 Posts: 3

It's been a while.
I made that's circuit again. but circuit didn't work.
https://flic.kr/p/2o5nYR7
Serial Port pinasign is

4 - red
5 - brown
7 -gray
8 - purple

The wires were aligned and checked with a tester to confirm that there was no problem.
and tester showed SDA=3.34V SCL=3.76V,MAX232EN Too Hot.

victor · S.F. Boss Joined: 07 Mar 2004 Posts: 2546 Location: Staff

I told already you the diodes are not sensed correctly.

I give up.
_________________
Victor Voinea
ALLservice HQ, Romania.

wpsx · Nou Venit Joined: 04 Nov 2022 Posts: 3

Sorry previous picture is hard to see.
I think black strip cathode towards the IC. is it wrong?
https://flic.kr/p/2o5tdb4

bob · Posted: Mon Dec 12, 2022 5:16 pm Post subject:

You know, we have those interfaces for sale, professionally built with 3.3V RS drivers and all. You should buy one It's just 45 Euro with shipping included worldwide and you will also support us by doing that.

Just send the payment via Paypal to support@allservice.ro, specify driven-i2c interface and email us a confirmation via email (this form actually https://www.allservice.ro/forum/dl/order-i.doc ).