Both ARM and DSP can control GPIO pins. Have the sending side set a GPIO pin (write a '1' to the SET register).
Have the receiving side clear that same GPIO pin (write a '1' to the CLR register). Use an oscilloscope to measure the pulse width (and it's jitter). When we started about a year ago, we measured about 900 usec using this method. We deemed that much to slow and created our own framework. Maybe the speed of the TI framework has increased in the meantime. Kind regards, Arie de Muijnck. ________________________________ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of kashin Lin Sent: Sunday, February 17, 2008 19:07 To: [email protected] Subject: About time evaluation in davinci dvm6446 (please give me somesuggestions) Hi, i want to evaluate the time interval between "ARM side sending some data" and "DSP side really receive those data( ready to process those data)" and vice versa. if i use following way to evaluate, it can just evaluate the time comsumed in "send" or "receive", not intervel from "sending" to "finish receiving". ARM or DSP side: start = get_time(); send_to_another_side(&data); end = get_time(); (can only get "end - start") due to above reason, i want to use the following way: ARM side DSP side start = get_time(); receive_data(&buff); send_data(&data); end = get_time(); but the essential condition is the "get_time" in both side must be in the same time domain. for instance, if "get_time" value is obtained by query OS timer counter respectively, then they aren't in the same time domain due to they(arm and dsp) use different timer as their OS timer. so i wonder is there any RTC (real-time counter) that shared by both side in Davinci? so that i can query "get_time" from it (the same time domain). or any idea about how to evaluate the time interval? thanks in advance. best, kashin lin -------------------------------------------------------- CONFIDENTIALITY NOTICE - This e-mail transmission, and any documents, files or previous e-mail messages attached to it may contain information that is confidential or legally privileged. If you are not the intended recipient, or a person responsible for delivering it to the intended recipient, you are hereby notified that you must not read this transmission and that any disclosure, copying, printing, distribution or use of any of the information contained in or attached to this transmission is STRICTLY PROHIBITED. If you have received this transmission in error, please immediately notify Arie Muijnck by telephone or [EMAIL PROTECTED] and delete the original transmission and its attachments without reading or saving in any manner.
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