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I NEED THE PORCESSOR TO RUN AT 82MHZ BUT THE XTAL IS 13>7242MHZ
HOW DO I PROGRAM C TO GET THE CODE FASTER?
I LOOK IN UVISION AND CHANGE THE FREQ BUT IT DOESNT MAKE CHANGE IN CODE! HAVE I GOT A BUG?
SORRY - JOKE [HA HA HA]
i mean sorry
it is a st number psd934f2
but it runs slow and i need more speed
That's better - but whatever made you think ALL CAPITALS was a good idea in the first place?!
The XTAL setting in uVision is only there so that the simulator can convert its instruction-cycle counts into times in seconds - it has no effect whatsoever on the compiler, assembler, or linker. Therefore, it has no effect whatsoever on the execution speed of your code!
How do you determine that "it runs slow"?
What, exactly, runs "slow"?
How much too "slow" is it? How much "faster" does it need to be?
What steps have you taken to ensure that this isn't due to inefficiencies in your own code?
What optimisation settings are you using?
Have you read the chapter in the Manual on writing optimum code? http://www.keil.com/support/man/docs/c51/c51_xc.htm
psd934f2 according to ST micro datasheet is a "configurable memory system on a chip for 8-bit microcontrollers"
and that obsolete chip has never neen intended for any use with a '51 other than a 'traditional' running at 12MHz.
Erik
ah yes - not to be confused with the modern uPSD range, which includes an 8051 in the package...
http://www.keil.com/dd/chips/stmicroelectronics/8051.htm