HP-IL with HP 82163A Video Interface

[brouhaha]

If you have a 41CX, or the Extended Function module on a 41C or 41CV (but NOT in a 41CX, it's built in), you can use XTOA to append any character by character code to the ALPHA register, though you can't use NUL characters (code 0) at the beginning of a string. If you needed a string ESC "7@" to send (not including the quotation marks), you could use CLA 27 XTOA ALPHA append 7 ALPHA 64 XTOA to compose it in ALPHA, since 27 is the character code of escape, and 64 is the character code of "@". All of the character codes are listed in an appendix in the Extended Function ROM manual and in the 41CX manual.