Olimex Support Forum

Others => UEXT => Topic started by: Arko on January 29, 2014, 02:41:29 PM

Title: MOD-WIFI and some I2C on same line
Post by: Arko on January 29, 2014, 02:41:29 PM
Hi guys,

After some research I found that we can put at most one RS232, one SPI, and multiple I2C on the same UEXT line. Am I right?

But what about the MOD-WIFI Module? In its schematics (https://www.olimex.com/Products/Modules/Ethernet/MOD-WIFI/resources/MOD-WiFi-RevA-schematic.pdf) it seem to use, or be connected to, all UEXT pins. Not only the SPI but also the RS and I2C.
Can we then use a UEXTx5 splitter to connect one MOD-WIFI and one or more I2C modules?

My specific targeted setup is to use a Olimexino-32U4 with one MOD-WIFI, one MOD-IO2 and one MOD-RTC on the same UEXT. Does that sound ok?

Thank you!
Title: Re: MOD-WIFI and some I2C on same line
Post by: LubOlimex on January 29, 2014, 04:43:44 PM
Hey Arko,

After some research I found that we can put at most one RS232, one SPI, and multiple I2C on the same UEXT line. Am I right?

Correct.

But what about the MOD-WIFI Module? In its schematics it seem to use, or be connected to, all UEXT pins. Not only the SPI but also the RS and I2C.
Can we then use a UEXTx5 splitter to connect one MOD-WIFI and one or more I2C modules?


No. MOD-WIFI uses SPI + two extra signals for interrupt and reset which are not I2C. While it can fit UEXT connectors the board needs more than SPI.

My specific targeted setup is to use a Olimexino-32U4 with one MOD-WIFI, one MOD-IO2 and one MOD-RTC on the same UEXT. Does that sound ok?

The WIFI module might be problematic. WIFI is generally not that easy to handle. OLIMEXINO-32u4 is not a bad board but it lacks the computing power for proper Ethernet or WIFI connection. I recommend you to first check the examples for the board and then make your choice.

Best regards,
Lub/OLIMEX
Title: Re: MOD-WIFI and some I2C on same line
Post by: Arko on January 29, 2014, 04:57:35 PM
Thank you for your answer Lub!

All clear, MOD-WIFI needs more than the SPI pins on the UEXT connector.

I'll check out the examples for implementation and see if it fits the 32U4 (my needs are really simple: small JSON response to an HTTP request).

If not, I might ramp up to the 328(Edit: same memory, less features. Doh!) or look at PIC32 solutions, but that's another platform...

thx
Best regards