This little bugger took me all night to complete!! BUT I learned a great deal in the process ! I hope that this program and all of the files with it, may be a of interest to you, and perhaps cause you to want to learn more about assembly language instructions, coding, the DEBUG functions, or some of the odd floating point instructions which were used to distinguish between the 386tm CPU and the 486tm CPU. I have included Appendix A of the _Intel486tm DX Microprocessor Data Book_ (c)1992, October, INTEL, which formed the basis of this program. I also consulted Dettmann and Johnson's, _DOS Programmer's Reference, 3rd Edition_ [(c)1992 by Que Corp.], pp. 33-39, on a few points. Two forms of a DEBUG script are included to help you learn how it can be used to create .COM (or even .EXE) programs from a DOS prompt. Lastly, a "dump" of all the code using Debug is also included. I claim NO rights to these files... if you like CPUID, use it; and maybe say hello on The CALL BBS (818) 352-1678. Daniel Sedory. Co- Sysop, and sometimes known as the Starman.