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<p>Hi everyone,</p>
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<p>I ran more tests, and removed prints from the ISR unless they went out of bounds for what we are expecting. The results were quite good - I did not see a latency greater than one microsecond on an hour run with a 1ms timer. Thanks for the pointers!</p>
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<p>Janet</p>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> users <users-bounces@rtems.org> on behalf of Thomas Doerfler (nt) <Thomas.Doerfler@imd-systems.de><br>
<b>Sent:</b> Thursday, December 8, 2016 10:58:45 PM<br>
<b>To:</b> users@rtems.org<br>
<b>Subject:</b> Re: 1kHz timer behavior on Cyclone V</font>
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<div class="PlainText">Hi,<br>
<br>
it's even worse: since the transfer of one character (8 bits) requires a<br>
leading startbit and a trailing stopbit (= total of 10 bits), you can<br>
only print 11.52 characters per 1ms.<br>
<br>
Am 09.12.2016 um 07:48 schrieb Sebastian Huber:<br>
> Hello Janet,<br>
><br>
> a printk() inside an ISR is quite bad. Lets assume it uses a serial<br>
> line with 115200 bits per second, then you can print 14.4 characters<br>
> per 1ms.<br>
><br>
<br>
<br>
-- <br>
IMD Ingenieurbuero fuer Microcomputertechnik<br>
Thomas Doerfler Herbststrasse 8<br>
D-82178 Puchheim Germany<br>
email: Thomas.Doerfler@imd-systems.de<br>
PGP public key available on request<br>
<br>
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