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(07-16-2017 02:05 PM)rprosperi Wrote: [ -> ]Are both HP-25 and -25C suitable for conversion?

Yes, all woodstocks will be suitable. And when I think right, the same circuit can also be used for the spice series HP-31/32/33/34/37/38, I will think about having a layout version for the next generation led calculators. As already said it will be ready at july 51st.

Bernhard
(07-16-2017 02:40 PM)PANAMATIK Wrote: [ -> ]
(07-16-2017 02:05 PM)rprosperi Wrote: [ -> ]Are both HP-25 and -25C suitable for conversion?

Yes, all woodstocks will be suitable. And when I think right, the same circuit can also be used for the spice series HP-31/32/33/34/37/38, I will think about having a layout version for the next generation led calculators. As already said it will be ready at july 51st.

Bernhard

What about a classic calculator that does all this? I would have to look into power consumption of the dispaly drivers, but I think this would be feasible. Your controller does have a DMA, doesn't it?
It should be possible to design a replacement PCB that requires no changes to the rest of the calculator.
(07-21-2017 09:19 AM)Harald Wrote: [ -> ]
(07-16-2017 02:40 PM)PANAMATIK Wrote: [ -> ]Yes, all woodstocks will be suitable. And when I think right, the same circuit can also be used for the spice series HP-31/32/33/34/37/38, I will think about having a layout version for the next generation led calculators. As already said it will be ready at july 51st.

Bernhard

What about a classic calculator that does all this? I would have to look into power consumption of the dispaly drivers, but I think this would be feasible. Your controller does have a DMA, doesn't it?
It should be possible to design a replacement PCB that requires no changes to the rest of the calculator.

Of course the Classic calculators and HP-67 can be included in the list of candidates. However no magnetic card reader supported.

AFAIK you have done already a replacement board for the classic calculators. However I would recommend the original display drivers to be removed, they are not necessary and consume too much power and would thwart the Low Power concept less than 0.2mA in Sleep Mode. Although your concept proposal would need less wires for doing the replacement.

Bernhard
(07-21-2017 03:43 PM)PANAMATIK Wrote: [ -> ]Of course the Classic calculators and HP-67 can be included in the list of candidates. However no magnetic card reader supported.

AFAIK you have done already a replacement board for the classic calculators. However I would recommend the original display drivers to be removed, they are not necessary and consume too much power and would thwart the Low Power concept less than 0.2mA in Sleep Mode. Although your concept proposal would need less wires for doing the replacement.

Bernhard

I agree that the original display drivers are not very helpful at all if you are aiming at low power. Standby as you have implemented it now won't be possible. Unless the controller had a way of shutting the display drivers down.
But the advantage of simply dropping in the replacement board without any soldering is huge in my opinion. I guess most people would be scared away by the amount of soldering involved.
(07-22-2017 12:00 AM)Geir Isene Wrote: [ -> ]
(07-15-2017 09:51 PM)PANAMATIK Wrote: [ -> ]Thanks Geir!

But there is a drawback: It will not be compatible with GPS Sad At least not this hardware configuration.

Bernhard

Why not?

Your question is a good example for expressing strong thoughts in only two words. I can distinctly hear also your demand for having GPS with the new Low Power HP-25 hardware.

Well, it is simple: I don't have any I/O port pins left in my prototype hardware. I had to use the RX receive line for driving the 12th display digit. Nothing left for controlling the GPS module.

But regarding the situation I think I should say "Why not!" as answer to your "Why not?". I will include the GPS feature in the final hardware, promised!

Bernhard
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