billw@hpcvra.CV.HP.COM (Bill Wickes) (12/05/89)
There have been a number of notes directed to me or about me, and the general topics of HP-28 SYSEVALs, code listings, etc. So let me see if I can respond to them all in a single note. First of all, for those gentle readers who don't know who I am, I was the software project manager for the HP-28C/S. Since coming to HP in 1981, I have directed the following projects: HP-41 Extended I/O ROM, HP-75 I/O ROM, HP-71 Math and Forth/Assember ROM (also the HP-41 Translator ROM, which I wrote myself as a after-hours project), and the RPL operating system, which underlies all current HP calculators with 2 or more display lines. In 1980, while an assistant prof of physics at U. of Maryland, I wrote Synthetic Programming on the HP-41C, which gave my name a lot of exposure in the calculator user community, and led to my current employment. It is important to note that Synthetic Programming was not in any way HP supported during its writing, although they did review it in HP Keynotes, which had a profound effect on the book's success. Since I was not an HP employee, I was free to say anything I pleased about the workings of the 41. Starting with the program code table that was published in the PPC Journal, all that was described in the book was derived by inference and experiment, without any access to HP documentation. Now, as an HP employee, I'm on the other side of the fence. I very much admire outsiders' efforts to decipher the 28 system, and am amazed at how much has been accomplished. I am sympathetic to requests that we publish lists of SYSEVAL addresses or better yet the full source code listings. There are two reasons why we haven't: * Competitive reasons. We flatter ourselves that there are some ideas and methods embodied in the 28 that our competitors might like to borrow. By not publishing commented listings, we at least make them work for it. * Support questions. We don't like to do things by half measures. We did publish and support the HP-71 source code, which was a major effort. To provide a comparable level of support for the 28 would be at least twice that effort, which we simply don't have the staff to do. There are about 9000 entry points in the 28 code, which requires 160 pages just to index. The printed listings, reduced 4-to-1 and printed double sided, are three inches thick. The only people here who are capable of providing external support are lab engineers, who have their hands full with other projects. 28 support is beyond the scope of our ordinary Customer Support group. The bottom line is that given the closed-box nature of the 28, it is not a good product for HP to invest in low-level system support. The group that reads these notes or is otherwise active in trying to push the 28 beyond the confines of the user-language is TINY compared to the masses of users who are happy with the calculator as is. Our limited active support resources are dedicated to the latter group. For those of you that are more ambitious, we can't offer much more than sympathy and encouragement. So, have fun (it is fun--or you wouldn't be doing it), and don't be too harsh in your thoughts about us here at HP. We're not trying to make life difficult for you, it's just that we don't have much time to help, either. --Bill Wickes
dan@Apple.COM (Dan Allen) (12/06/89)
I for one would like to thank Bill for his work on all of the projects that he has worked on. I have personally bought all of the various ROMs and calculators that he has managed/work on and it is to our advantage that HP has someone like Bill Wickes to help make great products. I would also like to thank Alonzo Gariepy for posting the many pages of information that he did about what he has discovered about the 28S. As I read through it all in the past day or two, I have found myself getting excited about the 28S like I got excited about Synthetic Programming years ago when Bill Wickes wrote his book. Let's all remember that such hacking is above all, FUN! Dan Allen HP Hacker