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+--- Thread: What are the final specs for the DM42? (/thread-9662.html)
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RE: What are the final specs for the DM42? - Helix - 12-17-2017 10:53 PM
Three more screenshots, to illustrate graphic capabilities:
http://www.silicium.org/forum/viewtopic.php?p=509730#p509730
Very nice!
RE: What are the final specs for the DM42? - rprosperi - 12-17-2017 11:08 PM
(12-17-2017 04:59 PM)Helix Wrote: You will find many screenshots in this french review:
http://www.silicium.org/forum/viewtopic.php?f=46&t=42544
Very nice review, thanks for sharing the link and also many thanks to the author. While I cannot read 100% of French, I can make out much of it; the topics and illustrations were both well chosen and well done.
It seems the author really liked his DM42!
RE: What are the final specs for the DM42? - larthurl - 12-17-2017 11:34 PM
(12-17-2017 11:08 PM)rprosperi Wrote:(12-17-2017 04:59 PM)Helix Wrote: You will find many screenshots in this french review:
http://www.silicium.org/forum/viewtopic.php?f=46&t=42544
Very nice review, thanks for sharing the link and also many thanks to the author. While I cannot read 100% of French, I can make out much of it; the topics and illustrations were both well chosen and well done.
It seems the author really liked his DM42!
thanks for the link. Great info.
My French is, well, non existent.
That's why I opened the link in Google Chrome and told it to translate haha
I can't wait to get the 42. Another week or so and I'll have it in my hot little hands.
.....Art
RE: What are the final specs for the DM42? - pier4r - 12-18-2017 07:22 AM
Nice link and nice active forum in general. They have nice discussions.
RE: What are the final specs for the DM42? - Logan - 12-19-2017 01:33 PM
So a quick question here:
I have been able to enlarge the font, and alter what elements of the stack are displayed, but is there any way as of yet to alter where the prompts are displayed? I find it a bit slow to glance up and down when I have both a soft menu, and a prompt on the screen with the stack in the middle of them. Ideally I would like to see the stack top aligned, the space for the soft key menu on the bottom, and then any prompts (or alpha display) in between those. That way my stack doesn't bounce up and down and I don't really need to look up at the top row.
Is there currently a way to do that through the virtual variables or something?
RE: What are the final specs for the DM42? - Massimo Gnerucci - 12-19-2017 02:46 PM
(12-19-2017 01:33 PM)Logan Wrote: So a quick question here:
I have been able to enlarge the font, and alter what elements of the stack are displayed, but is there any way as of yet to alter where the prompts are displayed? I find it a bit slow to glance up and down when I have both a soft menu, and a prompt on the screen with the stack in the middle of them. Ideally I would like to see the stack top aligned, the space for the soft key menu on the bottom, and then any prompts (or alpha display) in between those. That way my stack doesn't bounce up and down and I don't really need to look up at the top row.
Is there currently a way to do that through the virtual variables or something?
No, you can't.
RE: What are the final specs for the DM42? - Logan - 12-21-2017 02:39 PM
Maybe this is common knowledge (to beta testers), and undoubtedly everyone has read the quick-start guide thoroughly, but I thought it cool enough to share for those like me who didn't intuit this immediately:
So most know you can change the font size for the stack when you are on the home screen by pressing F6 (shift + F6 to go smaller).
But what doesn't seem immediately obvious is that you can also do the same when on the Program menu. At the smallest value, you can see 10 lines of code (default 8) and at the largest size you can see 5 lines of code.
I like that the two are independent, so I can say, display more lines of code but am not then also displaying a small-font stack (no benefit in making it smaller than it needs to be). Thanks to all the beta testers for introducing cool features like this!
RE: What are the final specs for the DM42? - Massimo Gnerucci - 12-21-2017 03:15 PM
(12-21-2017 02:39 PM)Logan Wrote: Maybe this is common knowledge (to beta testers), and undoubtedly everyone has read the quick-start guide thoroughly, but I thought it cool enough to share for those like me who didn't intuit this immediately:
So most know you can change the font size for the stack when you are on the home screen by pressing F6 (shift + F6 to go smaller).
But what doesn't seem immediately obvious is that you can also do the same when on the Program menu. At the smallest value, you can see 10 lines of code (default 8) and at the largest size you can see 5 lines of code.
I like that the two are independent, so I can say, display more lines of code but am not then also displaying a small-font stack (no benefit in making it smaller than it needs to be). Thanks to all the beta testers for introducing cool features like this!
Not only: you can even choose different font styles for stack and program list.
RE: What are the final specs for the DM42? - Logan - 12-21-2017 03:16 PM
Cool! Would that be through USB and the file structure?
RE: What are the final specs for the DM42? - grsbanks - 12-21-2017 03:18 PM
(12-21-2017 03:16 PM)Logan Wrote: Cool! Would that be through USB and the file structure?
No, you just select the font face (Shift-F5) and size (F6/Shift-F6) that you want, and that selection in PRGM mode is independent of what it is in stack mode.
RE: What are the final specs for the DM42? - Logan - 12-22-2017 02:12 PM
Quick question. I assumed it recharged through the USB port and have definitely seen one of the batteries go from three to four bars (and increase in displayed voltage) after being plugged in. Yet the battery itself is a CR2032 not LIR2032. An I imagining things? Coincidence?
RE: What are the final specs for the DM42? - rprosperi - 12-22-2017 02:27 PM
(12-22-2017 02:12 PM)Logan Wrote: Quick question. I assumed it recharged through the USB port and have definitely seen one of the batteries go from three to four bars (and increase in displayed voltage) after being plugged in. Yet the battery itself is a CR2032 not LIR2032. An I imagining things? Coincidence?
Like all batteries, under a heavy load (e.g. a long-running program) the CR2032 voltage will drop as a result of supplying the current, but once allowed to rest, the voltage level returns to (most of) its former level. So you can see the number of bars drop 4->3 when running, but then later return to 4 bars.
The firmware does some 'quieting' of this to prevent user concerns, but it can still happen when really long runs take place and/or when voltage is actually close to the 3/4 bar cut-off level.
When connected to USB, the cpu clock-speed increases dramatically and the system is powered from USB (and icon changes). So if you are running bizarre (to me) programs which run for hours, connecting it to USB first will not only avoid this issue, but also complete the job faster, since it's running at higher speed.
RE: What are the final specs for the DM42? - Logan - 12-22-2017 02:42 PM
Thanks Bob, I do understand these concepts. However I have also seen this voltage increase such as this morning: after resting all night in the same temperature. Battery was at 2.87V. Plug it in for 15 minutes and it's at 2.93V. No calculations have been run in 16 hours, no temperature changes. Also, the three bars were right out of the box. I understand temperature could affect voltage too but it seems very coincidental. Could leaving it on USB be raising a running average of voltage measurements? So it looks like it recharged but really it was just adding 3.07V of USB or whatever and raising the average?
RE: What are the final specs for the DM42? - rprosperi - 12-22-2017 03:34 PM
(12-22-2017 02:42 PM)Logan Wrote: Thanks Bob, I do understand these concepts. However I have also seen this voltage increase such as this morning: after resting all night in the same temperature. Battery was at 2.87V. Plug it in for 15 minutes and it's at 2.93V. No calculations have been run in 16 hours, no temperature changes. Also, the three bars were right out of the box. I understand temperature could affect voltage too but it seems very coincidental. Could leaving it on USB be raising a running average of voltage measurements? So it looks like it recharged but really it was just adding 3.07V of USB or whatever and raising the average?
Perhaps this is a result of the 'quieting' in the firmware? After a long period of rest, followed with external power, the battery likely has returned to it's 'full' voltage level, and the fw may be adding some offset which in this case is not needed. Just guessing...
My solution to distractions like this? I disabled the voltage display and opted for seeing just bars... Maybe I'm getting old
RE: What are the final specs for the DM42? - jebem - 12-22-2017 05:08 PM
(12-22-2017 02:42 PM)Logan Wrote: Thanks Bob, I do understand these concepts. However I have also seen this voltage increase such as this morning: after resting all night in the same temperature. Battery was at 2.87V. Plug it in for 15 minutes and it's at 2.93V. No calculations have been run in 16 hours, no temperature changes. Also, the three bars were right out of the box. I understand temperature could affect voltage too but it seems very coincidental. Could leaving it on USB be raising a running average of voltage measurements? So it looks like it recharged but really it was just adding 3.07V of USB or whatever and raising the average?
Interesting....
I do not own this unit and therefore I can't check the electronics diagram.
However, the voltage reading is not really being measured at the battery voltage terminals.
I think that what is being measured is the voltage at the power supply rail to the processor, because it is highly improbable that a dedicated battery voltage monitor is being used here.
So, connecting an external power source to the USB port, will raise the processor power supply a little and this extra energy is stored in the (at least) two large SMD capacitors visible in some youtube demo videos.
Removing the external power will continue to show a higher voltage for a while, because my guess is that this processor, being very efficient, is consuming very little current (how much, by the way?).
This is my best guess, unless there is a design flaw and the external power supply is being applied in parallel with the battery cell, but I don't even consider this possibility as it would be a gross mistake.
For dual power supply designs, the very minimum would be the usage of two low voltage drop rectifiers, where the cathodes are joined together and connected to the positive lead of the processor, and each rectifier anode receives a different power source. In this way, it is not possible to apply voltage from one source to another.
And because the external power source is a little higher (it must be) than the 3V of a coin cell, when using the external power source, it will in fact disable the usage of the internal coin cell.
So, how long can you see a voltage raise after unplugging the external power?