SPEED()
 A comparison value used to determine the processor speed
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 Syntax

     SPEED([<lMode>]) --> nCPUSpeed

 Argument

     <lMode>  If designated as .T., causes all interrupts, with the
     exception of the clock, to switch off..  The default value is "Leave
     interrupts on" (.F.).

 Returns

     SPEED() returns a percentage value to compare to a normal 4.77 MHz PC-
     XT, which corresponds to 100%.

 Description

     The function determines, in a precise fashion, the speed to compare to a
     4.77 MHz PC.  To make the measurement more precise, switch the
     interrupts off.  The only exceptions are the timer interrupts that
     refresh  working memory.

 Note

     Warning!  When you use the optional parameters to shut off all
     interrupts (with the exception of the timer interrupts) you cannot work
     simultaneously with the serial interface.  After you take the
     measurement, you can restore all interrupts.

 Examples

     .  For a normal AT:

        ? SPEED(.T.)         // 470  4.7 times PC

     .  Switch off interrupts in the same system:

        ? SPEED(.T.)         // 480  4.8 times PC