Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

How to craete a 1 microsecond interval Timer of HPS ?

What HWLIB APIs should I use to configure a Timer of HPS with a 1 micro-second interval ? How can I get the Timer Input Clock frequency and set the appropriate count into Timer ? Than...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Thanks.

I have modify the example project , to set a Timer with 20KHz / 80KHz ( 12.5us period), in Timer ISR, I will toggle the LED in FPGA side . So that I can measure the time with SignalTap-II.

OSC1_TMR0, 20KHz / 80KHz is fine, almost approached.

But when I send OSC1_TMR0 timer with 1 MHz, the result is slower than I expected. Why ? ( It should have 1us interval, but I measured 6.5us...)

[20KHz]

https://www.alteraforum.com/forum/attachment.php?attachmentid=9194

[80KHz]

https://www.alteraforum.com/forum/attachment.php?attachmentid=9195

[1M Hz]

https://www.alteraforum.com/forum/attachment.php?attachmentid=9193