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Limits of Indirect Addressing on the WP34S
Message #1 Posted by Namir on 1 Aug 2012, 9:37 a.m.

How high can I access general registers, using indirect addressing, on the WP34S? I would like to reach about 200. Is this possible?

Namir

Edited: 1 Aug 2012, 9:37 a.m.

      
Re: Limits of Indirect Addressing on the WP34S
Message #2 Posted by Walter B on 1 Aug 2012, 1:23 p.m.,
in response to message #1 by Namir

Yes :-) RTFM ;-)

            
Re: Limits of Indirect Addressing on the WP34S
Message #3 Posted by Namir on 1 Aug 2012, 3:44 p.m.,
in response to message #2 by Walter B

According to the manual, I cannot size the global registers to 200 or more. I am reading something wrong?

Namir

                  
Re: Limits of Indirect Addressing on the WP34S
Message #4 Posted by Walter B on 1 Aug 2012, 5:05 p.m.,
in response to message #3 by Namir

Hmmh, in your first posting you asked for "general registers" and my answer was yes. Now you ask for "global registers" and my answer must be no. See p.26 for address space and terms, p82 for LOCR, p.89 for REGS, and p.148 for the consequences. Get the maximum of 100 global registers with default memory layout, and allocate 100 local ones in addition via LOCR. Alternatively, you may specify REGS 60 and LOCR 140 as well.

                  
Re: Limits of Indirect Addressing on the WP34S
Message #5 Posted by Paul Dale on 1 Aug 2012, 5:08 p.m.,
in response to message #3 by Namir

No, local registers only over some threshold. Global registers stop at 100 (plus the 12 lettered) and cannot be increased beyond this.

- Pauli

Edited: 1 Aug 2012, 5:08 p.m.

                        
Re: Limits of Indirect Addressing on the WP34S
Message #6 Posted by Namir on 1 Aug 2012, 6:33 p.m.,
in response to message #5 by Paul Dale

Thanks guys. Sorry to hear about the limitation. I am trying to port program that uses large arrays from the HP-41CX emulator and the Free42 emulator. The latter allows me to create registers that run between 0 and 999.

:-(

Namir

                              
Re: Limits of Indirect Addressing on the WP34S
Message #7 Posted by Paul Dale on 1 Aug 2012, 6:38 p.m.,
in response to message #6 by Namir

That many registers requires at least four times the total available RAM on the 30b hardware.

- Pauli

                                    
Re: Limits of Indirect Addressing on the WP34S
Message #8 Posted by Katie Wasserman on 1 Aug 2012, 10:46 p.m.,
in response to message #7 by Paul Dale

What every happened to the idea of using some optional external, serial memory chip? Did anyone ever experiment with that on the 34s?

                                          
Re: Limits of Indirect Addressing on the WP34S
Message #9 Posted by Raymond Del Tondo on 1 Aug 2012, 10:54 p.m.,
in response to message #8 by Katie Wasserman

I think at a certain point it should be considered using a different hardware anyway.

A (hypothetical) 17bII+ Silver with Flash upgrade option comes into mind;-)

                                          
Re: Limits of Indirect Addressing on the WP34S
Message #10 Posted by Paul Dale on 1 Aug 2012, 11:13 p.m.,
in response to message #8 by Katie Wasserman

We haven't followed that path.

In theory a serial FRAM device could be attached to the SPI bus and then we'd have to see if this was fast enough to execute programs from. We worked out a few space for speed tricks that might have helped.

This would regain the backup and library flash segments (8kb) but not save any other code space (we can't push firmware into the fram easily). Plus it would cost firmware space to implement.

Waiting for Eric's DIY-5 seemed like a better option all around.

- Pauli

                                                
Re: Limits of Indirect Addressing on the WP34S
Message #11 Posted by Walter B on 2 Aug 2012, 3:50 a.m.,
in response to message #10 by Paul Dale

Quote:
Waiting for Eric's DIY-5 seemed like a better option all around.
+1! :-)
                        
Re: Limits of Indirect Addressing on the WP34S
Message #12 Posted by Namir on 1 Aug 2012, 11:53 p.m.,
in response to message #5 by Paul Dale

I am working on modifying my algorithm to replace the need to use an array of values, with calculating the array on the fly. The algorithm has some quirks regarding the number of array elements fitting a certain sequence. I promise you will see it at HHC2012. I am trying to create as many versions for different software and calculators as possible.

Namir

Edited: 1 Aug 2012, 11:53 p.m.


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