Search found 156 matches

by ijabbott
Mon Sep 09, 2019 7:48 am
Forum: Usage tips, tricks and problem reports
Topic: existencial problem STO/RCL ok, but EXISTS (?)
Replies: 5
Views: 319

Re: existencial problem STO/RCL ok, but EXISTS (?)

Flag 25 is the key to the problem. If flag 25 is set, then if an instruction cause an error, the instruction that causes the error is not executed and the flag is cleared. So you can do something like this: SF 25 RCL "Foo" FC?C 25 GTO "missing" @ or any other instruction If "Foo" exists, its value w...
by ijabbott
Thu Sep 05, 2019 10:33 pm
Forum: Software Library
Topic: RTC Calibration program
Replies: 20
Views: 1418

Re: RTC Calibration program

For me it is not totally clear from the instruction, whether I have to set the clock each time I do the calibration... You just need to know how much it has lost or gained since the last calibration, and the date of the last calibration (assuming the current date set on the calculator is correct), ...
by ijabbott
Mon Sep 02, 2019 7:40 am
Forum: Software Library
Topic: RTC Calibration program
Replies: 20
Views: 1418

Re: RTC Calibration program

Had a heck of a time creating the file in Win 10 with Notepad. Kept insisting on using a .txt extension instead of .cfg. Went back to an old MSDOS computer to create the file, then copied via floppy disk to my Win XT computer and then connected the DM42 to a USB port so I could copy it to the FAT d...
by ijabbott
Wed Aug 07, 2019 10:08 pm
Forum: Software Library
Topic: RTC Calibration program
Replies: 20
Views: 1418

Re: RTC Calibration program

I think the rtccalib.cfg value shown by the program possibly needs to be negated, or possibly the drift needs to be negated. I'm not sure which! On 2019-03-31 (beginning of EU summer time), I set the calculator to the correct time. On 2019-07-17 (108 days later), I noted my calculator had gained ab...
by ijabbott
Mon Jul 29, 2019 5:19 pm
Forum: Update Announcements
Topic: UPDATE: DMCP-3.15
Replies: 21
Views: 1588

Re: UPDATE: DMCP-3.15

So far so good! Two-key rollover response feels much improved compared to 3.14. But I have another small bug report: you forgot to give this minor firmware update version number 3.142. ;) Surely it should be 3.141, so the next minor update can append a 9? This reminds me of the version numbering of...
by ijabbott
Sun Jul 28, 2019 8:52 am
Forum: Software Library
Topic: RTC Calibration program
Replies: 20
Views: 1418

Re: RTC Calibration program

Also, when rounding to an integer, the program adds 0.5 and takes the integer part. That's okay for positive values, but is incorrect for negative values. (IP truncates towards zero, not towards negative infinity.) Is it well known that ENTER FP + IP correctly rounds to the nearest integer, even fo...
by ijabbott
Sat Jul 27, 2019 11:05 pm
Forum: Hardware
Topic: Case for Voyager 'L' size
Replies: 21
Views: 1755

Re: Case for Voyager 'L' size

Hard cases for storing portable 2.5 inch hard drives / SSDs are quite good, such as these ones by Inateck: https://www.amazon.co.uk/dp/B00L35UID0 https://images-na.ssl-images-amazon.com/images/I/717ouMlSEhL._SL1000_.jpg (I'm sure very similar cases are available with different brands.) The main down...
by ijabbott
Sat Jul 27, 2019 2:47 pm
Forum: Software Library
Topic: RTC Calibration program
Replies: 20
Views: 1418

Re: RTC Calibration program

Also, when rounding to an integer, the program adds 0.5 and takes the integer part. That's okay for positive values, but is incorrect for negative values. (IP truncates towards zero, not towards negative infinity.)
by ijabbott
Sat Jul 27, 2019 12:50 pm
Forum: Software Library
Topic: RTC Calibration program
Replies: 20
Views: 1418

Re: RTC Calibration program

I think the rtccalib.cfg value shown by the program possibly needs to be negated, or possibly the drift needs to be negated. I'm not sure which! On 2019-03-31 (beginning of EU summer time), I set the calculator to the correct time. On 2019-07-17 (108 days later), I noted my calculator had gained abo...
by ijabbott
Tue Jul 23, 2019 7:28 am
Forum: Software Library
Topic: ? DM42 as Alarm Clock ?
Replies: 16
Views: 621

Re: ? DM42 as Alarm Clock ?

It's probably technically feasible on the DM42 from a hardware point of view (using the STM32's RTC alarm capabilities), but probably a lot of effort from a software point of view.