DM48n

[M0R33z]

Double CPU speed and double flash memory !

This is certainly also very interesting for the DB48x

[Steve Simpkin]

And much more RAM available to the DM42. Aprox 415K on the DM42n vs ~32K on the DM42.
https://www.hpmuseum.org/forum/thread-22...#pid191773

[toml_12953]

(09-17-2024 03:54 PM)Steve Simpkin Wrote:  And much more RAM available to the DM42. Aprox 415K on the DM42n vs ~32K on the DM42.
https://www.hpmuseum.org/forum/thread-22...#pid191773

I have a DM42 (n is on order) and have a few programs in it. I still have 73784 bytes of memory free. Are you sure about the 32K figure?

[Steve Simpkin]

(09-18-2024 12:12 AM)toml_12953 Wrote:  

(09-17-2024 03:54 PM)Steve Simpkin Wrote:  And much more RAM available to the DM42. Aprox 415K on the DM42n vs ~32K on the DM42.
https://www.hpmuseum.org/forum/thread-22...#pid191773

I have a DM42 (n is on order) and have a few programs in it. I still have 73784 bytes of memory free. Are you sure about the 32K figure?

I was going by what Bob Prosperi reported in the post I referenced. He may have had a lot of programs/data on his DM42.

[rprosperi]

Tom is right, a DM42 with an empty state file has about 74K of available RAM. The number I reported in the other thread was simply how much my daily use DM42 had available when I grabbed it. Just last night I checked both devices with a new, blank state file:

DM42 CAT MEM => 75,640 bytes (empty state file)
DM42n CAT MEM => 455,988 bytes (empty state file)

[toml_12953]

(09-18-2024 08:54 AM)rprosperi Wrote:  Tom is right, a DM42 with an empty state file has about 74K of available RAM. The number I reported in the other thread was simply how much my daily use DM42 had available when I grabbed it. Just last night I checked both devices with a new, blank state file:

DM42 CAT MEM => 75,640 bytes (empty state file)
DM42n CAT MEM => 455,988 bytes (empty state file)

I love those first three words!

All that extra RAM is one reason I ordered the n! (That's not n factorial)

[c3d]

(09-17-2024 02:59 PM)M0R33z Wrote:  Double CPU speed and double flash memory !

This is certainly also very interesting for the DB48x

To the point where you titled your thread DM48n and not DM42n. I appreciate the compliment ;-)

[M0R33z]

(09-18-2024 09:29 PM)c3d Wrote:  

(09-17-2024 02:59 PM)M0R33z Wrote:  Double CPU speed and double flash memory !

This is certainly also very interesting for the DB48x

To the point where you titled your thread DM48n and not DM42n. I appreciate the compliment ;-)

small mistake but thanks :-)

[jeanwilson]

What I'm wondering is, will db50x running on the DM42n suffer the same speed penalty as when running on the DM32? Because currently db48x which runs on the DM42 is currently 2 times faster than db50x on the DM32 (see https://www.hpmuseum.org/forum/thread-97...e%20plenty) which nevertheless benefits from a processor which is supposedly twice as fast! Even if the DM32 and DM42n share the same hardware, do they share the same speed limitation (especially since they will both be based on DMCP5, I believe)? Or is it a matter of principle that makes the DM32 run twice as slowly as the DM42?

Tell us when you can clarify the situation.

[jeanwilson]

What I'm wondering is, will db50x running on the DM42n suffer the same speed penalty as when running on the DM32? Because currently db48x which runs on the DM42 is currently 2 times faster than db50x on the DM32 (see https://www.hpmuseum.org/forum/thread-97...e%20plenty) which nevertheless benefits from a processor which is supposedly twice as fast! Even if the DM32 and DM42n share the same hardware, do they share the same speed limitation (especially since they will both be based on DMCP5, I believe)? Or is it a matter of principle that makes the DM32 run twice as slowly as the DM42?

Tell us when you can clarify the situation.

[Nigel (UK)]

(09-20-2024 01:56 AM)jeanwilson Wrote:  What I'm wondering is, will db50x running on the DM42n suffer the same speed penalty as when running on the DM32? Because currently db48x which runs on the DM42 is currently 2 times faster than db50x on the DM32 (see https://www.hpmuseum.org/forum/thread-97...e%20plenty) which nevertheless benefits from a processor which is supposedly twice as fast! Even if the DM32 and DM42n share the same hardware, do they share the same speed limitation (especially since they will both be based on DMCP5, I believe)? Or is it a matter of principle that makes the DM32 run twice as slowly as the DM42?

Tell us when you can clarify the situation.

The times in the post you link to date from March this year. It was in March that DMCP5 was updated to allow the processor frequency to increase when on USB power. Assuming that the timings were done on USB power the processor frequencies in the test would have been 80MHz for the DM42 and 48MHz for the DM32. If done today on USB power the DM32 frequency would be 160MHz and the results should reflect this.

Since I don’t actually have a DM32 I can’t be sure that this is correct.

Nigel (UK)

[c3d]

(09-20-2024 09:09 AM)Nigel (UK) Wrote:  

(09-20-2024 01:56 AM)jeanwilson Wrote:  What I'm wondering is, will db50x running on the DM42n suffer the same speed penalty as when running on the DM32? Because currently db48x which runs on the DM42 is currently 2 times faster than db50x on the DM32 (see https://www.hpmuseum.org/forum/thread-97...e%20plenty) which nevertheless benefits from a processor which is supposedly twice as fast! Even if the DM32 and DM42n share the same hardware, do they share the same speed limitation (especially since they will both be based on DMCP5, I believe)? Or is it a matter of principle that makes the DM32 run twice as slowly as the DM42?

Tell us when you can clarify the situation.

The times in the post you link to date from March this year. It was in March that DMCP5 was updated to allow the processor frequency to increase when on USB power. Assuming that the timings were done on USB power the processor frequencies in the test would have been 80MHz for the DM42 and 48MHz for the DM32. If done today on USB power the DM32 frequency would be 160MHz and the results should reflect this.

Since I don’t actually have a DM32 I can’t be sure that this is correct.

Nigel (UK)

I can actually confirm this, though with a caveat: after the upgrade, you cannot unplug the USB while DB48X is running without turning the calculator off, otherwise there is a power loss and you end up rebooting with a blank state. I'll investigate.

The good news is that on USB, the DM32 now runs the NQueens benchmark in 450ms down from 1800ms (and roughly 1300 for the DM42 on USB). Yay! So as long as you remember to switch the calculator off before unplugging, everything is fine!

I'll update the performance benchmarks page for the DM32 after that upgrade.

[Nigel (UK)]

(09-30-2024 03:19 PM)c3d Wrote:  I can actually confirm this, though with a caveat: after the upgrade, you cannot unplug the USB while DB48X is running without turning the calculator off, otherwise there is a power loss and you end up rebooting with a blank state. I'll investigate.

An issue with USB power that sounds similar to this is mentioned in this thread on the SwissMicros website. It seems that the problem only applied to early DM32s and that even for these there is a fix.

Nigel (UK)