- My new Casio Prizm
- 25 Oct 2013 01:40:59 pm
- Last edited by gbl08ma on 26 Oct 2013 04:59:48 am; edited 1 time in total
Recently, my Casio Prizm became a hard brick (would not turn on, not even for "emergency OS updater" modes) and had to have its motherboard replaced. I paid nothing. Thanks Casio for having a three year warranty (my calc broke the day after its second anniversary), you're awesome. Oh wait, maybe you're not so awesome. I'll explain.
As you probably know, Casio makes two models of the Prizm: the fx-CG 10 and the fx-CG 20. The 10 is sold mostly in the Americas, and the 20 in Europe and Asia. These two models are absolutely the same, inside and outside, except for two things: the model label and the fact that the CG 10 can't open g3p files not "provided by Casio" or created on the calculator (with the screen capture feature or using the Geometry add-in, for example).
Whether a calculator is a CG 10 or 20 is defined by some bytes in the lowest flash sector, where the bootloader resides. This area should never be modified, and not even OS updates so far change a thing in it.
As a owner of a fx-CG 20, I could view any g3p picture with it. I could include g3p pictures, created on the computer with Casio's converter, inside eActivity files, and all was well. That was, until the day the calculator had to be repaired.
The repair consisted of replacing the motherboard, and all the data I had on the previous one was irrecoverable - the only way anyone could recover it meant going to the point of desoldering the flash chip to read it with an external reader, mounting the relevant parts of the memory as a FAT filesystem, and copying my files to the new motherboard.
The result: now I got a Prizm that's new on the inside, but has the old shell, screen and keyboard. And I lost everything I didn't back up (mostly things I didn't need, so that's not a big problem).
I noticed one thing when I got the calculator back: it would not read eActivity files with g3p images ("type invalid" error) nor any non-Casio-provided g3p file. That is, just like a fx-CG 10.
I was already suspecting this would happen, because some time ago a friend had to get her Prizm repaired too, and the same thing happened to her. However, because the calculator was not mine I could never fully investigate.
Both calculators now show, on the "System" menu, a strange version number that differs from the usual 01.04.0200 (for CG 20) or 01.04.0100. Mine is 01.04.3201. Also, the versions for the "messages" on mine are all 01.05. This is ahead of other calculators with OS 01.04 installed. I didn't notice any difference in the messages but obviously they may exist.
Using an in-development version of Utilities, triple-checked to ensure it would not break any calculator again (still, who knows?) that has a System Information screen, displaying several strings from the device's memory, including from the bootloader, I got this:
(the source code used to obtain this screen can be found here)
So yes, my calculator is definitely a fx-CG 10 that says fx-CG 20 on the case. The "true" OS version, i.e. the one not modified for display on the "System" menu, is the same as on every other calculator with OS 01.04: 01.04.0000. The last four bytes are modified by the OS depending on the calculator model, and perhaps some other flags too (explaining my strange version number).
Also note how the PCB model is 755A instead of 755D.
I believe this is meant to indicate this is a PCB that was used as a replacement. I'm fully OK with that... just as long as my calculator had the same features it had before the repair, that is, being a fx-CG 20 and not a fx-CG 10!
I don't exactly need the g3p viewing feature, except to open the eActivity files I had created with built-in images, because of the JPEG Image Viewer I developed. Still, I'm going to bother Casio Europe and Ename (their tech support representatives in Portugal, who did the repair) with some emails.
This doesn't quite justify sending my calculator back for another "repair", and I really don't feel like running an "OS update" sent by Casio to rewrite the bootloader (as if they would do that...), but at least I'll let them know they are turning fx-CG 20s into CG 10s and that's illegal here (since you're effectively getting, as the result of a in-warranty repair, a product with less features than the original ones).
As you probably know, Casio makes two models of the Prizm: the fx-CG 10 and the fx-CG 20. The 10 is sold mostly in the Americas, and the 20 in Europe and Asia. These two models are absolutely the same, inside and outside, except for two things: the model label and the fact that the CG 10 can't open g3p files not "provided by Casio" or created on the calculator (with the screen capture feature or using the Geometry add-in, for example).
Whether a calculator is a CG 10 or 20 is defined by some bytes in the lowest flash sector, where the bootloader resides. This area should never be modified, and not even OS updates so far change a thing in it.
As a owner of a fx-CG 20, I could view any g3p picture with it. I could include g3p pictures, created on the computer with Casio's converter, inside eActivity files, and all was well. That was, until the day the calculator had to be repaired.
The repair consisted of replacing the motherboard, and all the data I had on the previous one was irrecoverable - the only way anyone could recover it meant going to the point of desoldering the flash chip to read it with an external reader, mounting the relevant parts of the memory as a FAT filesystem, and copying my files to the new motherboard.
The result: now I got a Prizm that's new on the inside, but has the old shell, screen and keyboard. And I lost everything I didn't back up (mostly things I didn't need, so that's not a big problem).
I noticed one thing when I got the calculator back: it would not read eActivity files with g3p images ("type invalid" error) nor any non-Casio-provided g3p file. That is, just like a fx-CG 10.
I was already suspecting this would happen, because some time ago a friend had to get her Prizm repaired too, and the same thing happened to her. However, because the calculator was not mine I could never fully investigate.
Both calculators now show, on the "System" menu, a strange version number that differs from the usual 01.04.0200 (for CG 20) or 01.04.0100. Mine is 01.04.3201. Also, the versions for the "messages" on mine are all 01.05. This is ahead of other calculators with OS 01.04 installed. I didn't notice any difference in the messages but obviously they may exist.
Using an in-development version of Utilities, triple-checked to ensure it would not break any calculator again (still, who knows?) that has a System Information screen, displaying several strings from the device's memory, including from the bootloader, I got this:
(the source code used to obtain this screen can be found here)
So yes, my calculator is definitely a fx-CG 10 that says fx-CG 20 on the case. The "true" OS version, i.e. the one not modified for display on the "System" menu, is the same as on every other calculator with OS 01.04: 01.04.0000. The last four bytes are modified by the OS depending on the calculator model, and perhaps some other flags too (explaining my strange version number).
Also note how the PCB model is 755A instead of 755D.
I believe this is meant to indicate this is a PCB that was used as a replacement. I'm fully OK with that... just as long as my calculator had the same features it had before the repair, that is, being a fx-CG 20 and not a fx-CG 10!
I don't exactly need the g3p viewing feature, except to open the eActivity files I had created with built-in images, because of the JPEG Image Viewer I developed. Still, I'm going to bother Casio Europe and Ename (their tech support representatives in Portugal, who did the repair) with some emails.
This doesn't quite justify sending my calculator back for another "repair", and I really don't feel like running an "OS update" sent by Casio to rewrite the bootloader (as if they would do that...), but at least I'll let them know they are turning fx-CG 20s into CG 10s and that's illegal here (since you're effectively getting, as the result of a in-warranty repair, a product with less features than the original ones).