|29C needs help!|
Message #1 Posted by Dieter on 11 Mar 2011, 5:19 p.m.
A few days ago I acquired a HP-29C in nice condition for a good price. Aaah... red LEDs. So small and handy - it's a real cutie, isn't it? :-) The battery compartement has been modified so that the unit now runs on regular AA-size NiMH batteries, providing about five times the original operation time and allowing the use of a decent processor-controlled external charger. So far, so good.
First tests showed that the 29C runs significantly faster than my good old (even slightly newer) 34C. So I tried the 8-queens-benchmark on http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=700 to find out more.
Since the 29C is not listed there I used the sample program for the 11C/34C, only slightly modified for the 29C since it uses register 0 for indirect addressing. The result was quite surprising: While the 34C is listed with 73 minutes, the 29C did the job in just 42! Even better, a simple factorial program (i.e. essentially a simple loop) runs quite exactly twice as fast as on the 34C. I had expected an execution speed close to that of the HP-67, or maybe something comparable to the 34C/15C.
Today there was another surprise. The 29C was running a program when, after about half an hour, I suddenly noticed the display showed nothing but twelve zeros: "000000000000" and no reaction on any key press. :-(
Now, there are two questions:
- The calculator worked perfectly for a few days. What might have happened here? What can I do now?
- I wonder if the 29C really is so much faster than the 34C or even the 67. Maybe other 19C or 29C-users may try the 8-queens-benchmark program and state their results. Has my unit possibly been modified? In this case, may this have caused the mentioned problem?