Generation of 18k square wave

How to generate the 18kHz sqaure wave using 8051

 RE: Generation of 18k square wave

Easy: just toggle a port pin once every 28ms!

 RE: Generation of 18k square wave

Now, here are the links to the so-called "bible" for the 8051 - see what you can find that might enable you to toggle a port pin once every 28ms:

Chapter 1 - 80C51 Family Architecture:
http://www.nxp.com/acrobat_download/various/80C51_FAM_ARCH_1.pdf

Chapter 2 - 80C51 Family Programmer's Guide and Instruction Set:
http://www.nxp.com/acrobat_download/various/80C51_FAM_PROG_GUIDE_1.pdf

Chapter 3 - 80C51 Family Hardware Description:
http://www.nxp.com/acrobat_download/various/80C51_FAM_HARDWARE_1.pdf

Also check the datasheet for the particular chip that you're using - it may have other useful features...

 RE: Generation of 18k square wave

28uS :-)

 seconds - not siemens!

Actually, 28us !! ;-)

 RE: seconds - not siemens!

even easier:
use the PCA
of course, if you insist on using some antique or 'simple' chip, that does not apply

Erik

reference:
The PCA cookbook
http://www.intel.com/design/mcs51/applnots/270609.htm