Beta 41CL --> Best CL UTILs to burn in NoVRAM 64?


I will try not to ask tons of questions here, but since I google search for answers on this site, someone else may find the question helpful with an answer. :-)

I have a first batch 41CL that did not have the CL UTILS module pre-installed. What version of the CL UTILS is best?

Then, assuming that answer, I believe it changes if I am taking advantage of the Library 4 project?

So, which with and which without the Library 4? Thanks in advance.


Easy answers Gene:

1. Best version of CLUTLS w/out Library4: CLUTLS_2H

2. Best version of CLUTILS with Library4: CLUTLS_4H

2. Best version of CLUTLS with Library4 *and* bank-switched: POWERCL_BS

All are V1 (a.k.a the Beta version), V2 and V3-compatible.

I'll seriously recommend you use the POWERCL module, not only because it has more in it but also because the code is optimized and corrects a few glitches present int the others.

Manuals are posted in Monte's CL site, in the "Other Docs" section.



Sorry for changing the topic, but this thread has both of the Users, Gene and Angel, that have commented on different ways of powering the CL41. So here are my questions:

How *bad* (or good?) really is the power usage of the CL, concerning the CL's 110 microamp standby current draw compared to the original's 10 microamp draw? I realize it's a subjective question, but how much time can you get/go until the BAT annunciator comes on?

Gene: Can you provide info on the rechargeable N-cell batteries and charger that you're using? I'm curious of the brand/model, time between charges, and any pros and cons you've discovered. Thanks.

Angel: I like the idea of the 5 volt power you apply through a sacrificial module - utilizing the housing and it's terminals to power the CL through an unused port. I assume you have also have batteries in the calculator when your power adapter is plugged in, so are they rechargeable, or regular alkalines? I assume they are rechargeables. Can you elaborate on the batteries you're using and what module (a *common* Memory module?) you used to make up the power connection?

Thanks guys - and anyone else is invited to comment. Again, I apologize for changing the topic.


Edited: 30 June 2012, 6:20 p.m.


Hi Matt,

I "sacrified" a memory module once to get external power for my HP41s.

There are some shortcomings concerning feeding the halfnut versions. Also, I have made only experiences with LR1 alkalines being resindent in the calculator. There is no trouble leaving them in the calc during external powering. I noticed some battery drain at power-off of the calc when the power adapter was left conected without being in the power outlet.

I think there is no problem using rechargeables during operation of the HP41. However, I am not sure about the currents when the calc is off and I can only speculate about two disadvantageous extremes: either the current would be very low resulting in long charging times, or it might be pretty high which could be dangerous for the circuitry.




Matt, the USB power guru is Diego - I just use his solution.

I can tell you however that it works flawlessly on Fullnuts, ergo on the CL as well, with or without batteries (rechargeables or not).

If I´m correct the batteries are used as the primary source when they´re present with the USB power plugged. Even then there´s an important safety function performed, so you won´t run out of juice during a critical flash-write action.

Also there is no battery charging capability, as it has a zener diode directing the current out and not into the batteries.



First of all, SORRY Diego, I had you in mind, when I addressed my question to Angel. No excuses <embarrassed> I MESSED UP. Thank you Angel.

Thank you Frido for the link to your solution. I'm not sure how I missed that thread. Great information.

Angel, thanks for pointing out that the external power is not a means of recharging the batteries, as the port's intended purpose is to supply power TO a module.

Now I need to incorporate Monte's serial port connector into the same module housing as the power connection. I'll need to mount a female mini-USB port into the module, with Monte's connector next to it.

This a great forum!


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