SCUBA - Nitrox and Trimix for HP-41

[4ster]

(09-14-2016 09:20 PM)Dieter Wrote:  

(09-14-2016 04:25 PM)4ster Wrote:  My second hobby lately has been rediscovering my HP-41. I wrote this to support my first hobby.

A few remarks:

1. CLRGX is a CX function and not available on other '41 calculators. Instead of 0,004 CLRGX you should simply use CLX STO 01 STO 02 STO 03 STO 04. That's just five bytes and thus even requires less memory than the CLRGX version. And, more important, it runs on any 41.

2. There are several XEQ 13 calls that obviously are used to display output. But there never is a return from this subroutine as it ends with a jump to LBL 00 (prompt for next input). I looks like you meant GTO 13 in every case that now reads XEQ 13. Or, to be honest, simply replace the two occurences of "XEQ 13" by a simple AVIEW GTO 00. This does the same and it's shorter and faster. After this LBL 13 can be removed completely.

The same is true for the XEQ 12s. In both cases this should be GTO 12.

3. The CLA in line 08 is not required. And why do you set flag 29 in line 7 and clear it directly afterwards (without any operation where flag 29 makes a difference)?

4. I don't know anything about diving, but this sounds like a useful program. So why don't you post it to the HP41 Software Library? After some minor changes... ;-)

Dieter

Dieter,

Thanks for the input.

CLRGX - You are correct. I had an issue running the program on the iphone 41C app that halted the program at the CLRGX instruction with a NONEXISTENT and assumed that it was because CLRGX was an extended memory function. I looked it up after I wrote the post and was hoping to edit the original post before anyone noticed. :-)

I'll edit the CLRGX and XEQs and replace them with GTOs in the original post.

After all these years I am still confused when CLA is needed and when its not. So I tend to put too many in. Flag 29: Since normal flow in the program is to halt at the PROMPT, it is likely that it leaves flag 29 set, instead of having to reset it outside the TRIMIX program. Your right, it's fluff and SF 29 is no longer in the listing.

I wasn't sure what the policy is on adding programs to the libraries. There are some really good programs in there and I didn't want to litter the space. After a few days residing here for more improvements, I'll copy the program over to the HP-41 library if there are no objections.