Pic16f877 I/O & A/D

Guest · Guest

Hi,

I've got an existing little project that is configured for all analog (eight A/D's) on a pic 16f877. I'd like to see if I couldn't use this existing project and add a mux to it to expand the number of A/D inputs. I've got ports A2, E1, and E2 available for the channel selects. Is it possible to set these as output I/O's where they can be swung high or low and leave the existing a/d inputs? Do I use the set_tris() function?

Thanks.

valemike · Guest

Yes you can use tris settings to select the 3 select pins. Set them as outputs.

However, I don't think you can get more A/D inputs with a Mux (?) since i thought a mux only works with logic levels.

There are some PICs out there with several more ADC channels if that interests you.

mkent · Joined: 09 Sep 2003 Posts: 37 Location: TN, USA

Maxium makes TTL/CMOS controlled analog mux's. Try this link
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2064
Good luck, Mick

guest · Guest

Thanks for the replies.

I was thinking about using this one from Analog Devices.

http://www.analog.com/en/prod/0%2C2877%2CADG608%2C00.html

SC · Guest

I need help is there someone who would like to give me some sample experiments. for specific, how to display my result in a/d conversion to LCD.