Path: utzoo!ncc!alberta!ihnp4!ihlpf!nevin1 From: nevin1@ihlpf.ATT.COM (00704a-Liber) Newsgroups: comp.sys.handhelds Subject: Re: Undocumented functions Message-ID: <3624@ihlpf.ATT.COM> Date: 5 Feb 88 16:31:04 GMT References: <3255@super.upenn.edu> Reply-To: nevin1@ihlpf.UUCP (00704a-Liber,N.J.) Organization: AT&T Bell Laboratories - Naperville, Illinois Lines: 22 In article <3255@super.upenn.edu> mallow@linc.cis.upenn.edu.UUCP (Eric Mallow) writes: > Does anyone know of any undocumented functions on either the HP-25, >TI-59, or HP-28c? Are there any undocumented features involving the >TI-59/PC-100C printer combination, or TI-59 card reader? One of the undocumented opcodes on the TI-58/59 (I think it was 48) would allow you to modify the printer registers directly. The way you enter this opcode is by going RCL 48 in program mode, then go back and delete the RCL. When this opcode is printed, it prints as "HIR", and the next line is the register number you want to modify (such as HIR 01). These registers only had ten digits of precision (as best as I remember it), and would store non-negative integers only. You could do some of the things you could do with normal registers, such as multiply into them, etc. Although I originally discovered this undocumented function I did not know the full extent of what you could do with it until I read about it in a TI-58/59 newsletter. -- _ __ NEVIN J. LIBER ..!ihnp4!ihlpf!nevin1 (312) 510-6194 ' ) ) "The secret compartment of my ring I fill / / _ , __o ____ with an Underdog super-energy pill." / (_