WP34 resets when using Y^X

[Randy]

The subject says it all. When I attempt to use Y^X, the WP34 resets.
I have tried reflashing with the latest 3.2(Printer)3472 with no change.
This happens on both of my 34s.
I must have something set wrong.

Randy

[Paul Dale]

Check your batteries? That function is pretty compute heavy and will push the device to full clock speed for the duration and with marginal batteries that can cause problems.

I use that function a lot and it doesn't cause a reset for me, so there is something weird going on.


- Pauli

[Randy]

You are correct sir.
The batteries measure 3.0 volts and the new ones are 3.2.

I'm supposed to know this stuff!

Thanks

[Jonathan Cameron]

What is the minimum "safe" voltage of the WP-34s?

From the manual I see that batteries with voltage less thatn 2.8 V should be replaced. But this thread seems to hint 2.8 V may not be enough. I received refurbished HP-30b units from ebay and they all had a voltage of 3.0 V. I'm wondering what the life will be on these units and whether I should consider replacing the batteries immediately (if the nominal new voltage is more like 3.2 V).

-Jonathan

[walter b]

(02-28-2014 06:07 PM)Jonathan Cameron Wrote:  What is the minimum "safe" voltage of the WP-34s?

From the manual I see that batteries with voltage less thatn 2.8 V should be replaced. But this thread seems to hint 2.8 V may not be enough. I received refurbished HP-30b units from ebay and they all had a voltage of 3.0 V. I'm wondering what the life will be on these units and whether I should consider replacing the batteries immediately (if the nominal new voltage is more like 3.2 V).

Hmmh, what is "safe"? If you call SAVE every once and a while, everything is voltage-break safe on the WP 34S. Also compare p. 44 and the voltages mentioned there.

d:-)

[Randy]

I will admit that I measured my batteries with a high-z meter, about 10^10 Ohms. So, they are probably lower voltage under load.

Strange, that I could not cause a reset with anything other than Y^X. I know Pauli said this function is compute heavy but I'm surprised it would reset even with a 2 in both X and Y. It just happens very fast.

Moral to the story, keep spares on hand.

Randy

[Paul Dale]

Logarithms might do it -- try log y to base x. The zeta function is usually a sure fire battery stresser.

Setting SLOW mode is often beneficial for the batteries.


- Pauli

[Marcus von Cube]

You should measure the voltage under load. A short loop with BATT (and no PSE) will force the calculator to run at full speed and thus BATT should report the voltage under load. Give it some time (a few seconds) before you stop the loop with R/S. The reason is the adaptive approach of the battery level detecting algorithm. The processor just features a brown out detector.