Discussion in "General help Guidance and Discussion" started by    RUSHI D    Apr 28, 2009.
Tue Apr 28 2009, 04:13 AM
#1
hi frnz...!

can u pls list down d differences between SPI and I2C protocols...

regards
rushi d.
Tue Apr 28 2009, 05:50 AM
#2
I2C =>less no. of pins only one line for data transfer
SPI=>two lines required for data transfer
I2C is slower than SPI.
Tue Apr 28 2009, 07:14 AM
#3
thanx shyam...

but i want detailed differences like if we r compairing their speeds den mention d max speeds they can achieve

any more difference...

regards
rushi d.
Tue Apr 28 2009, 07:32 AM
#4
There are a lot of difference from the protocol point of view. But Hardware wise it same as mentioned by shyam.

1. In I2C lot of s/w manipulation has to be done. where as in SPI programmer need to handle only SS pin if SPI is used between multiple ics.

2. I2C can reach only till 384kbps based on CCLK. Whereas SPI can go till CCLK/4. i.e., if CCLK=12MHz, Then SPI speed is 3MHz.

3. There are atleast 30-40 situation which programmer is suppose to handle in I2C for effective and efficient communication. where as in SPI only SS is suppose to be managed and data is supposed to be placed in SPDAT.

4. In SPI since both the MOSI(Master Out Slave In) and MISO(Master In Slave Out) uses a single buffer care should be taken to transfer the data.

5. I2C can be used in a situation where shrinking of the pcb is more important than speed and SPI is vice-versa

 RUSHI D. like this.
Tue Apr 28 2009, 07:41 AM
#5
I2C can go upto 4Mhz SPI can go upto 70Mhz
 RUSHI D. like this.
Tue Apr 28 2009, 07:42 AM
#6
thanx ajaz 4 ur reply

but i did not get 3rd pt..

can u explain..?
Tue Apr 28 2009, 07:57 AM
#7
He mens to say that, incase of I2C programmer has to take care of right sequence of data transfer on bus like address, start, stop, ack, nak etc...
where as in case of SPI just SS (slave select) is to be managed and data read/write is done from SSPDAT register.

these names may vary from controller to controller
Tue Apr 28 2009, 12:47 PM
#8
k got it...
thanx ajay
Tue Apr 28 2009, 06:10 PM
#9
A very valuable tool to discovering what things mean and what things do is the Google search engine.

If you type into this search engine the phrase "SPI interface", your first website shown is:
http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus

This is a pretty good description of the SPI interface, and some of what it can do...

Likewise, if you type in "I2C interface", you get this website:
http://en.wikipedia.org/wiki/I%C2%B2C

Give it a try, and see for yourself...

Hope this helps,

Get Social

Information

Powered by e107 Forum System

Conversation

Sun Sep 25 2016, 04:41 AM
mira
hi sir, could you help me regarding simple multiplication calculator?it should be include with buzzer. i use dragonplus. please
ExperimenterUK
Sat Sep 24 2016, 05:49 PM
@Rus Ans .. what project ?
ExperimenterUK
Sat Sep 24 2016, 05:48 PM
@engr1931 depends on type of scanner
engr1931
Sat Sep 24 2016, 03:07 PM
Is it possible to send data from 2 barcode scanner to pc using serial port using 8051?
Wed Sep 21 2016, 02:22 AM
Rus Ana
can anyone help me for my project? T.T
Fri Sep 09 2016, 02:54 PM
Sarath babu
8051 a/c motor speed control
Tue Aug 30 2016, 05:03 PM
Kinzang
hello sir, can i know more in detail about the football substitution board project.
Tue Aug 30 2016, 06:06 AM
bhagyashri buddhewad
my project is automatic room light controller using visitor counter so i want coding in keil and circuit diagram can tell me and i want to use uc at89c51 thanks you
ExperimenterUK
Sun Aug 28 2016, 08:32 PM
Which project ?
Sun Aug 28 2016, 05:21 AM
Dipankar Baishya
Hi sir.... I want do this project but I have not this sercuit diagram..... can you give me full details and diagram...... Thank you

Downloads

Comments

ak_pan
Thu Sep 08 2016, 06:28 PM
martinsnc115877
Sat Aug 20 2016, 01:44 PM
rajavarmanslr
Thu Aug 18 2016, 12:24 PM
CASINODIGITAL
Mon Aug 15 2016, 09:04 PM
mariahcarey
Sat Aug 06 2016, 11:38 AM
dann11
Thu Jul 28 2016, 09:43 PM
adithyapaip
Thu Jul 21 2016, 05:45 PM
celu
Thu Jul 21 2016, 05:27 PM

Online

Guests: 47, Members: 0 ...

most ever online: 182184
(Members: , Guests: 182184) on 06 Aug 2010: 05:37 AM

Members: 37781
Newest member: ak_pan
Forum Activity
martinsnc115877 Avatar
Posted By martinsnc115877
Wed Sep 14 2016, 12:51 PM
sir, i did your led scrolling mass display, and it...
ExperimenterUK Avatar
Posted By ExperimenterUK
Fri Sep 09 2016, 11:45 PM
The Hex file for this project is a bit too big for...
rajavarmanslr Avatar
Posted By rajavarmanslr
Thu Aug 18 2016, 01:40 PM
I have two 8051 that interfaces with nRF24l01. One...
rajavarmanslr Avatar
Posted By rajavarmanslr
Thu Aug 18 2016, 12:31 PM
I have two 8051 that interfaces with nRF24l01. One...
ExperimenterUK Avatar
Posted By ExperimenterUK
Mon Aug 01 2016, 05:26 AM
is working nowugoo5000Great, thanks for letting u...
ugoo5000 Avatar
Posted By ugoo5000
Sat Jul 30 2016, 07:31 AM
is working noworg 00hmov p1,#11111111bmov p3,#1111...
ugoo5000 Avatar
Posted By ugoo5000
Sat Jul 30 2016, 06:40 AM
when i press a button in p3.0,the counter will st...
ugoo5000 Avatar
Posted By ugoo5000
Sat Jul 30 2016, 06:30 AM
proteus file Attachment ...
ExperimenterUK Avatar
Posted By ExperimenterUK
Fri Jul 29 2016, 11:34 PM
Your code does not count at all, it produces a one...
ugoo5000 Avatar
Posted By ugoo5000
Fri Jul 29 2016, 07:49 PM
i want the the counter to be counting in secs with...