Search found 320 matches

by Thomas Okken
Sat Mar 16, 2019 9:30 am
Forum: Usage tips, tricks and problem reports
Topic: MVAR vs INPUT
Replies: 5
Views: 213

Re: MVAR vs INPUT

No, hsilop is referring to the way the menu behaves when VARMENU is active. Normally, STO and RCL will show a menu with all the currently existing variables, but while VARMENU is active, you get that menu instead. For example, say you start from the Memory Clear state, and you enter a program with 0...
by Thomas Okken
Sat Mar 16, 2019 2:51 am
Forum: Update Announcements
Topic: UPDATE: DMCP-3.13 / DM42-3.13
Replies: 16
Views: 562

Re: UPDATE: DMCP-3.13 / DM42-3.13

On my Mac, I tried copying the latest help file to /Volumes/DM42/HELP, from the Desktop, using the Finder. It stared at its navel for a suspiciously long time, and then the Finder reported Unexpected Error 100006, the disk disappeared, and the DM42 froze. After poking its reset hole, it was complete...
by Thomas Okken
Fri Mar 15, 2019 12:30 am
Forum: Software Library
Topic: PUSH/POP stack
Replies: 4
Views: 1138

Re: PUSH/POP stack

→ is one of the matrix editor's cell movement commands. It stores the contents of the X register in the current cell, moves the cell pointer one to the right, and puts the contents of that next cell in X. It is roughly equivalent to STOEL J+ RCLEL. If all that is Greek to you, I recommend reading th...
by Thomas Okken
Thu Mar 14, 2019 11:39 pm
Forum: Software Library
Topic: External stack
Replies: 6
Views: 150

Re: External stack

What registers are used by statistical functions? The statistical functions use numbered registers (which in turn are stored in the matrix variable REGS). By default it uses registers 11 through 23, as follows: 11: ΣX 12: ΣX↑2 13: ΣY 14: ΣY↑2 15: ΣXY 16: N 17: ΣLN(X) 18: ΣLN(X)↑2 19: ΣLN(Y) 20: ΣLN...
by Thomas Okken
Thu Mar 07, 2019 4:46 pm
Forum: Discuss!
Topic: DM 48 .... WHY NOT ?!!!
Replies: 54
Views: 7361

Re: DM 48 .... WHY NOT ?!!!

They would make Free42 operating more RPL-like and I'm uncertain whether this is an advantage or the opposite. RPL is a beautiful design in and of itself (its tendency to lead to write-only stackrobatics notwithstanding), but it doesn't mix well with the HP-42S design, in my opinion. I was never a ...
by Thomas Okken
Thu Mar 07, 2019 4:27 pm
Forum: DM42
Topic: Intel library 2.0u2
Replies: 11
Views: 451

Re: Intel library 2.0u2

And now, after lots of thought, you know what the comment should be. Thus, now's the time to record it ;) What I should have written in the first place was this: // In core_commands6.cc static int mappable_acos_r(phloat x, phloat *y) { if (x < -1 || x > 1) return ERR_INVALID_DATA; if (!flags.f.rad)...
by Thomas Okken
Wed Mar 06, 2019 11:38 pm
Forum: DM42
Topic: Intel library 2.0u2
Replies: 11
Views: 451

Re: Intel library 2.0u2

David, thanks for elaborating. The fixes you made to the Intel library for your other project, do you also apply them when building the DM42 firmware? If so, would Free42 benefit from these fixes as well?
by Thomas Okken
Wed Mar 06, 2019 2:10 pm
Forum: DM42
Topic: Intel library 2.0u2
Replies: 11
Views: 451

Re: Intel library 2.0u2

I don't write a lot of comments, but a good rule is always: if the code does something that isn't obvious, or for reasons that aren't obvious, there should be a comment. I the case in question, the acos bug in 2.0u1, the Free42 code is correct, but not well commented: static int mappable_acos_r(phlo...
by Thomas Okken
Wed Mar 06, 2019 11:18 am
Forum: DM42
Topic: Intel library 2.0u2
Replies: 11
Views: 451

Re: Intel library 2.0u2

Thomas_ER wrote:
Wed Mar 06, 2019 10:21 am
@Thomas:
maybe David needs a direct mail.
Both visit the forum probably rarely.
That's OK, this is not an urgent question. I don't need a reply within 24 hours or anything. I'm just curious.
by Thomas Okken
Wed Mar 06, 2019 12:54 am
Forum: Software Library
Topic: Moon Landing on DM42?
Replies: 5
Views: 224

Re: Moon Landing on DM42?

Over at the MoHPC, there is the Moon Lander from the HP-25 ( link ), with explanation and instructions. It's pretty easy to port to the HP-42S: 00 { 90-Byte Prgm } 01▸LBL "ML" 02 500 03 STO 00 04 -50 05 STO 01 06 120 07 STO 02 08▸LBL 00 09 FIX 04 10▸LBL 02 11 RCL 00 12 1ᴇ4 13 ÷ 14 RCL 01 15 X<0? 16 ...