Started by Alan KM6VV in AT91SAM ARM10 years ago 2 replies

Hi, I've been looking for I2C, and haven't found it on the AT91. I did, however find TWI. Is it the same? Similar? I've not worked with I2C...

Hi, I've been looking for I2C, and haven't found it on the AT91. I did, however find TWI. Is it the same? Similar? I've not worked with I2C before; but I am familiar with SPI. This project calls for I2C; I'll be interconnecting several processors and perhaps a peripheral or two. Thanks, Alan KM6VV


AT91SAM9263 TWI (I2C) interface to RTC......

Started by Kiran in AT91SAM ARM8 years ago 3 replies

Dear All, Any one tried working with TWI (I2C) in AT91SAM9263. I have interface TWI to RTC (DS1338). If TWI is enbled there no O/P from...

Dear All, Any one tried working with TWI (I2C) in AT91SAM9263. I have interface TWI to RTC (DS1338). If TWI is enbled there no O/P from these pins(PB4 & PB5), how ever if these pins are configured as GPIO & I2C run in software, it is working fine. Can any one tell me about H/W TWI (I2C). Regards, Kiran


can i use I2C with 89C52?

Started by adnan in AT91SAM ARM12 years ago 1 reply

hi u all i m having problem here that whether I2C standard support 89C52 or not or in the other meanings that 89C52 does not ocntain SDA...

hi u all i m having problem here that whether I2C standard support 89C52 or not or in the other meanings that 89C52 does not ocntain SDA line.. althoug getting data serially from controller... looking for ur kind replies.. regards.. Sheikh Adnan


Re: TWI == I2C?

Started by Alan KM6VV in AT91SAM ARM10 years ago 1 reply

Hi Tim, Rick, Thanks! I wondered if it was a patent thing. And I hadn't thought of looking on Wiki. Now to check for any examples! Alan ...

Hi Tim, Rick, Thanks! I wondered if it was a patent thing. And I hadn't thought of looking on Wiki. Now to check for any examples! Alan KM6VV > From: martin_tim > Sent: Monday, October 15, 2007 10:36 AM > =20 > According to the Wikipedia acticle on I2C: > =20 > TWI (Two Wire Interface) is essentially the same bus implemented on > various system-on-chip processors from Atmel and o


TWI bus pull-ups

Started by chipburnssc in AT91SAM ARM12 years ago 1 reply

If I want to use the TWI (I2C) bus, do I need to include the standard 4.7k pull-ups on the TWCK/TWD lines or will the SAM7 internal pull-ups...

If I want to use the TWI (I2C) bus, do I need to include the standard 4.7k pull-ups on the TWCK/TWD lines or will the SAM7 internal pull-ups do the trick? I have actually included a Linear Technology LTC1694 I2C 'Accelerator' on the board (I'm building it now) but I'm not sure if I should install it at this point. Any comments? Thanks


Interfacing MPU6050 and AT91SAM7 using i2c protocol

Started by "ank...@gmail.com [AT91SAM]" in AT91SAM ARM3 years ago 1 reply

Hello, I am facing a problem in interfacing mpu6050 and AT91SAM7SE-EK using i2c protocol. I wanted to read temperature from a register of ...

Hello, I am facing a problem in interfacing mpu6050 and AT91SAM7SE-EK using i2c protocol. I wanted to read temperature from a register of MPU6050 but I am unable to do so. I did the following in my code: 1. Enabled the clock for twi 2. disabled the gpio pin and enabled the A-select register 3. Open drained the pins 4. cwgr value =0x2FFFF 5. mmr with the slave address 0x68, mread and 1 byt...


PECS board available - SAM7 + Ethernet, JTAG, I2C

Started by Brad Parker in AT91SAM ARM11 years ago 1 reply

I created a simple SAM7 based cpu box for a customer a while ago. You can view it at http://www.silicontkx.com/PECS.htm. It's...

I created a simple SAM7 based cpu box for a customer a while ago. You can view it at http://www.silicontkx.com/PECS.htm. It's interesting because it has a large CPLD connected to the SAM7 and an ethernet chip. It can speak JTAG and I2C externally and is designed to control a number of lines on a switch evaluation board. It might make a re


how can i correct this code??

Started by sheikh adnan in AT91SAM ARM12 years ago 2 replies

hi.. i m trying to write READ/ WRITE code for 24C64 with I2C standard, using 89c52, i m implementing my own I2C but having trouble with the...

hi.. i m trying to write READ/ WRITE code for 24C64 with I2C standard, using 89c52, i m implementing my own I2C but having trouble with the code below that it does not read any charachter. here is the code for this written in KEIL micro vision.. #include        // Header file for the 89C52 MCU #include


I2C driver

Started by Pierre Laviolette in AT91SAM ARM11 years ago 4 replies

I managed to get my driver to work but had to use a "sledge hammer" solution. THEre is a question below. I write to EEPROM, this works...

I managed to get my driver to work but had to use a "sledge hammer" solution. THEre is a question below. I write to EEPROM, this works fine. After that the EEPROM is busy for a while. To determine if the EEPROM is finished I start a read operation (the first part of this is a write) which is to be aborted until I get an answer. Anyway I see the writes going out on the wire on the l...


SAM7 TWI/I2C driver read (24xxx EEPROM)

Started by Pierre Laviolette in AT91SAM ARM11 years ago 2 replies

Hi, Does anybody have a driver for SAM7. I have my own and write works fine, but read does not work properly; it only works once....

Hi, Does anybody have a driver for SAM7. I have my own and write works fine, but read does not work properly; it only works once. Anyways, I am investigating, but in the meantime I thought I'd post in case someone has a working example;this could save me some time. Thanks in advance. Pierre.


i2c driver on AT91SAM7S-EK (using FreeRTOS)

Started by Gabriele Brosulo in AT91SAM ARM10 years ago 3 replies

Hi all, It's again me, whith another issue :) I'm trying to use a eeprom with my evaluation board (the one in the subject), so I added the...

Hi all, It's again me, whith another issue :) I'm trying to use a eeprom with my evaluation board (the one in the subject), so I added the code from the atmel site (AT91-AN01: Using the Two-wire interface (TWI) in Master Mode on AT91SAM Microcontrollers) to my adjusted version of FreeRTOS, the one we talked about just a few message below. In order to make things working, I have added ...


AT91SAM7-64 and TWI (i2C) with FM24C64

Started by mr_rossi_1 in AT91SAM ARM12 years ago 5 replies

Hello. I have some probloems with my AT91 and a fram i connected via the TWI. I am using the sample code from the atmel-homepage....

Hello. I have some probloems with my AT91 and a fram i connected via the TWI. I am using the sample code from the atmel-homepage. unfortunately i have some trouble with the code. I am not able to read or write information into the fram. con anybody give me an sample of a twi implementation? thx MrRossi


Detecting absence of I2C bus devices

Started by Peter Wintulich in AT91SAM ARM11 years ago 5 replies

Hello, I have an interesting problem with the TWI in the at91sam7s64. I am trying to detect the absence of a device on the TWI bus. I had...

Hello, I have an interesting problem with the TWI in the at91sam7s64. I am trying to detect the absence of a device on the TWI bus. I had expected to receive a NACK in the status register upon sending the device address. Insted I received 0xFF data back and no error in the twi_sr. 1) is there something I am missing. 2) is there a correct procedure for detecting the absence of a device o


Problem reading eeprom on AT91SAM7S-EK

Started by Gabriele Brosulo in AT91SAM ARM10 years ago 2 replies

Hi all, trying to read an i2c eeprom, my code loop in the following while: [code] ? ?pPIOA-> PIO_CODR = LED1; // turn LED on ? ?while...

Hi all, trying to read an i2c eeprom, my code loop in the following while: [code] ? ?pPIOA-> PIO_CODR = LED1; // turn LED on ? ?while (!(status & AT91C_TWI_RXRDY)){ ? ? ? ? ? ? status = AT91C_BASE_TWI-> TWI_SR; ? ? ? ? ? ? if (status){ ? ? ? ? pPIOA-> PIO_CODR = LED3; // turn LED on ? ? ? ? AT91F_AT24C_WaitMicroSecond(10000); ? ? ? } ? ? ? else{ ? ? ? ? pPIOA-> PIO_SODR = LED3; // t