I'm trying to use this to convert rs232 levels from my gsm modem to 5v TTL. I was struggling to get it working. So I devised a test to see if I even got any form of communications. My custom Arduino is based on duemilanove design hence it uses ft232rl. I've unplugged my arduino chip. Now I'm just using the ft232rl ttl pins which are connected to max232. I've connected the T1OUT to R1IN. My theory is I can create a loop back so I should get back whatever I send using the terminal within arduino IDE. I've double quaduple checked my connections using sparkfun and various other sites. But nothing happens. Why?
I get 8.5v on pin2 and -7.5 on pin 6 and according to the datasheet thats within spec. I've powered it using 5v. I've decoupled the VCC.
If you could come up with some common pitfalls with this chip, I will be extremely grateful. Btw I don't have a rs232 port on my pc.