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UART voltage level lower than 3.3v?


#1

Hi,

I have a UART device that is listed in the manual as;

[quote]Electrical Level: TTL level,
Output Voltage Level: 0V~2.85V [/quote]

Is that 2.85v level too low for it to work with my Cerbuino? I’m not getting a response from it and I’m wondering if that is the problem.

Thanks


#2

2.85 should be fine. What kind of device, do you have a link? Are you sure you have wired it correctly?


#3

OK, thanks.

It’s a GPS receiver;

http://www.usglobalsat.com/store/download/46/em406a_ug.pdf

It’s powered up and getting a fix but it’s connected via an Arduino shield so buzzing out the TX and RX connections is my next job if the TTL levels aren’t an issue. The pinouts on all the schematics match up fine, but you never know.

The only other thing that stands out is the comment in the pdf for the receiver for it’s RX pin;

I wonder if they mean for the operation of the UART comms? I’m thinking that I could set it high from one of the Cerbuino’s spare digital IOs.