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Hello,

I was wondering whether to choose a 20b or 30b for converting the calculator to a WP34s.

What would the reasons the be to pick one over the other?

Thanks in advance.

Elite
(11-16-2014 06:33 PM)Elite Wrote: [ -> ]Hello,

I was wondering whether to choose a 20b or 30b for converting the calculator to a WP34s.

What would the reasons the be to pick one over the other?

Thanks in advance.

Elite

The 30b has a better keyboard - it has a firm "click" feel to it. The 20b keyboard has no click and feels a little soggy. On the other hand, on some 30b machines some keys can "click" without registering a press, sometimes. You may feel happier with a non-click keyboard that forces you to push firmly.

The 20b is black, which makes for a neater appearance when the black overlay is applied.

I believe that neither machine is being manufactured any longer. I have found it easier to get hold of the 30b here in the UK than the 20b.

Apart from the keyboard and the case colour I believe that the hardware in both machines is identical.

I prefer the look and feel of the 30b myself. I think most will agree with me.

Good luck with the WP34s. You'll love it!

Nigel (UK)
Thanks,

It's just that where I live, Germany, the 20b is three euros cheaper than the 30b.

In the manual it also says that, however on pictures the keybords look the same.

I think Ill just go with the 30b.

Elite
There must be a hidden feature in both machines that allows HP's original firmware to detect the hardware it is running on. The enhanced features of the 30b aren't available on the 20b even if you load the 30b flash image on it.
How did you load a 30b Flash Image into a 20b or vice versa? Can you revert a WP34S into a 30b again?
(11-18-2014 04:22 AM)PANAMATIK Wrote: [ -> ]How did you load a 30b Flash Image into a 20b or vice versa? Can you revert a WP34S into a 30b again?

You just need the correct flash image.
AFAIK you cannot read the original flash image from the 30b calculator, because it is protected. Perhaps somebody has found a way of reading it though. This would be interesting. Anyway, I do not intent to re-repurpose my WP34S.

Bernhard
(11-18-2014 10:14 PM)PANAMATIK Wrote: [ -> ]AFAIK you cannot read the original flash image from the 30b calculator, because it is protected.
In order to get access to the flash contents you'll need to reactivate the SAM-BA boot loader of the chip. The original firmware does not support this. I don't know whether the access path through the JTAG connector is blocked. IIRC, one of the configuration bits of the Atmel chip can be used to lock out JTAG access to the flash.

Luckily, we have friends to help us out... Smile
(11-17-2014 06:43 PM)Marcus von Cube Wrote: [ -> ]There must be a hidden feature in both machines that allows HP's original firmware to detect the hardware it is running on. The enhanced features of the 30b aren't available on the 20b even if you load the 30b flash image on it.

On the HP50G, HP49G+, HP49G, and HP48GII, there is an opcode that behaves differently on each machine with allows assembly software to detect the type of machine. Perhaps something similar exists for these calculators?
For my understanding, there is the same Atmel processor in the 20b and in the 30b,so same opcodes there (?) ... Just my 2cents

Best regards
Ralf
(11-22-2014 08:40 AM)workspace Wrote: [ -> ]For my understanding, there is the same Atmel processor in the 20b and in the 30b,so same opcodes there (?) ... Just my 2cents

This is correct, the difference lies elsewhere.

There is some ROM in the CPU which might be different, there might be something different on the PCB.


- Pauli
(11-22-2014 08:43 AM)Paul Dale Wrote: [ -> ]There is some ROM in the CPU which might be different, there might be something different on the PCB.

Two crossed pins under the epoxy blob.
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