The new HP Voyager (HP12c, HP15c Collector's Edition)calculators have a connector in the battery bay that can be used to change its firmware. Theconnector is that 6-pin set just below the batteries. The previous version had the same connector, and it needed a special cable to do programming with it; however, the previous version had a TTL-level adaptor chip, and is not pin-compatible with the current connector - which runs a USB protocal (albeit with a completely different connector!).
I have tried hard to find the connector to buy or produce such cable, but after looking everywhere for it, I've been unable to get one, or even to order one for production. Now, apparently, there were close to 1000 units of the previous version produced by HP for the 2011 production run. These can be used, but they need to be changed to use the new pin mapping required for the USB connection. I will describe the cable changes in a future blog issue.
there could be another solution, but that involves more effort: you need to open the machine and solder a USB connector in a place designed for it. Only the nano-connector applies!
Why all this fuzz? because using it, you can alter the original firmware to get more memory ! there are instructions of what positions to change in the program memory to increase the memory, and also the palces to tamper to avoid problems with the MEM screen and program limits. You can find them in hpmuseum.org . Be careful with what you do because you can brick the calculator !
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