hp 41 synthetic programming


I tried to figure out how to do this instruction : STO IND O
but I did not find how :(

(it is the instruction 28 from the main program from this --> http://www.hpmuseum.org/software/41/41crmat.htm)

Someone can help me out?

Thank you :)


Have you created the program Load Bytes, or the byte jump key assignment?

All synthetic lines must be created manually by manipulating memory through tricks or automated programs such as LB (loadbytes).

I just state the above and ask if you have a knowledge base for sythetic programming?

Otherwise, it would be a long and drawn out process if LB or any other form of sythetic byte production is not immediately available.

Cheers, Geoff


cf. HP-41C Synthetic Programming

As stated in the description of the program you can avoid synthetic programming:

N.B:   Synthetic registers M N O can be replaced by R01 R02 R03 but, in this case, delete line 31, replace line 02 with 0 STO 01 RDN in the following listing and choose bb > 03.

I recommend to give it a try, though.

how to do this instruction : STO IND O

Only now I've realized that you might already have succeeded to enter STO O and you just have a problem with this specific command. Enter the following program and execute GTO . . (PACKING):


Now you go to the ENTER line and execute the byte-grabber, which will leave the sequence:

91: STO
31: STO 01
32: STO 02
33: STO 03
34: STO 04
35: STO 05
36: STO 06
37: STO 07



Edited: 14 May 2011, 7:51 a.m.


cf. HP-41C Synthetic Programming
The byte code table linked there at http://www.hpmuseum.org/prog/synth.gif appears to be the one Synthetix put out in 1982 as a quick-reference card (same fonts, arrangement of what's in each little box, etc.), except that Synthetix' had color coding of boxes for instruction length, and the structure of multi-byte instructions on the right. I wonder if that's posted somewhere. I got my start in synthetic programming in the book "Extend your HP-41" using the byte grabber, but later got the ZENROM which lets you key the synthetic instructions directly in, so for example to get STO IND O you just press STO <shift> . O

Same book, green cover. Read it back to front and again and again.

Created the byte jumper and then Load Bytes and then carded the LB. Never looked back. All my HP41CX programs contain sythetics.

Cheers, Geoff

sure got used to seeing "MEMORY LOST" !!!!!!



I would never have found this.

Thank you :)


Or get hold of a Zenrom or one of the other ROMS that support synthetics... I believe that the PPC ROM has some support? I have to say that I love my Zenrom, makes things just a whole lot easier.


PPC rom has the load bytes as well as a few other synthetic programs.


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