REG(<C register name>)
 Examines the contents of CPU registers.
 Returns <expC> contents of specified register as hex string.

 Valid register names are AX, BX, CX, DX, SP, BP, SI,
                          DI, DS, ES, CS, IP, and FF.

 Returns null if a register name is invalid.

 To get contents of the byte registers (AH, AL, BH, BL,
 CH, CL, DH, DL), take the substring of the full register.

         REG("AX")         returns "FF55" in AX
 SUBSTR( REG("AX"), 1, 2 ) returns "FF"   in AH
 SUBSTR( REG("AX"), 3, 2 ) returns   "55" in AL


             Placed in the Public Domain by Tom Rettig Assoc.