MSefi.com read only forum (Jan.15,2018)

Understood. Thanks for your help.

In the "How Megasquirt Works" section (http://www.megamanual.com/v22manual/mfuel.htm#reqfuel), about half-way down the page (several paragraphs following the fuel equation) it's explained that

"For example, in a pretty reasonable worst case, 1500 Hz is about 4 times the IRQ ("interrupt request ...