Hi Andris, Thx for your reply. I will give it a try. However, even 50KHz won't result in so much delay. Under 50KHz, it takes 20 microsecond (us) to tx one byte, isn't it? For simple read or write operation, data plus protocol overhead (START, STOP, and ACK), total bytes transmitted may be just around 10, the delay should be less than 1 millisecond (ms). Is it due to the tinyos task scheduling? Well, I am just guessing. If it has sth to do with task scheduling, I want to try another way: is it possible to use native I2C c driver in stead of tinios module just like using wdt_enable(1) to do system reset? I guess the driver is already somewhere. Can you tell me how to use?
Thx & Best Regards dajiang ________________________________________ From: András Bíró [[email protected]] Sent: Thursday, 28 March, 2013 4:52:49 AM To: He Dajiang (I2R) Cc: [email protected] Subject: Re: [Tinyos-help] tinyos efficiency Hi, TinyOS uses 50kHz I2C, but you can use 100kHz i2c on most devices and 400kHz on some. Unfortunatly, there's no nice way to change the bitrate, you must change it in /tos/chips/atm128/HplAtm128I2CBusP.nc (TWBR register) Andris Institute for Infocomm Research disclaimer: "This email is confidential and may be privileged. If you are not the intended recipient, please delete it and notify us immediately. Please do not copy or use it for any purpose, or disclose its contents to any other person. Thank you." _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
