Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

What is the difference between two serial communications SPI and I2C ?

Status
Not open for further replies.

alexz

Full Member level 5
Joined
Nov 19, 2004
Messages
283
Helped
6
Reputation
12
Reaction score
3
Trophy points
1,298
Location
UK
Activity points
2,246
What is the difference between the 2 serial communications SPI and I2C (I squared C) ?
 

alexz

Full Member level 5
Joined
Nov 19, 2004
Messages
283
Helped
6
Reputation
12
Reaction score
3
Trophy points
1,298
Location
UK
Activity points
2,246
Re: SPI v/s I2C

When a slave has got the SPI interface and a master has got the I2C interface,
is it possible to communicate between them by combining the 2 interfaces?
 

Jos Brink

Member level 3
Joined
Jan 28, 2004
Messages
64
Helped
9
Reputation
18
Reaction score
2
Trophy points
1,288
Activity points
577
Re: SPI v/s I2C

no.:cry:

I²C uses 2 lines. and is bi-directional

SPI uses 3 lines.. MISO MOSI SCK
 

alexz

Full Member level 5
Joined
Nov 19, 2004
Messages
283
Helped
6
Reputation
12
Reaction score
3
Trophy points
1,298
Location
UK
Activity points
2,246
Re: SPI v/s I2C

It is written in the data sheet of the ADC AD7694 from analog devices that it has got the SPI output. But that chip has got only 2 lines : SCLK and SDO.

Added after 3 minutes:

Quote from the data sheet:

Serial Data Output. The conversion result is output on this pin. It is synchronized to SCK.

Serial Data Clock Input. When CNV is low, the conversion result is shifted out by this clock.
 

Jos Brink

Member level 3
Joined
Jan 28, 2004
Messages
64
Helped
9
Reputation
18
Reaction score
2
Trophy points
1,288
Activity points
577
Re: SPI v/s I2C

it is a SPI bus. only in one direction.. if you clock it.. it shifts the data out on the SDO pin.. in spi terms MISO (Master in Slave out.) asuming that your controller is a master.
Connect this pin to your controllers MISO pin an tie the SCL to the clock. You need an extra enable line for the CNV line. On avrs you could probably use the SS line.. but i'm not sure on that.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top