In SX Microcontrollers, SX/B Compiler and SX-Key Tool, John Kauffman wrote:

[3]I am trying to figure out the time resolution for resolving two near-simultaneous triggers on two pins of an SX.[/3]

<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p>[3] [/3]</o:p>

[3]As I understand a B pin trigger, the following sequence occurs:[/3]

[3]Pin has WKEN=0 set at start[/3]

[3]Pin is triggered [/3]

[3]SX changes its WKPND to 1[/3]

[3]SX immediately shuts off any other pin from being set to WKPND=1[/3]

[3]SX begins ISR[/3]

<o:p>[3] [/3]</o:p>

[3]I am wondering about the timing of "immediately" in the above sequence. [/3]

[3]Does that shut-off occur on the very next clock cycle? [/3]

[3]If yes, when using the internal 4Mhz clock that would mean a second trigger would be locked out provided it was at later by at least 1 / 4,000,000 seconds = 250 nanoSeconds?[/3]

<o:p>[3] [/3]</o:p>

[3]Thanks.[/3]

---------- End of Message ----------


You can view the post on-line at:
http://forums.parallax.com/forums/default.aspx?f=7&p=1&m=154791

Need assistance? Send an email to the Forum Administrator at forumadmin@parallax.com

The Parallax Forums are powered by dotNetBB Forums, copyright 2002-2006 (http://www.dotNetBB.com)