Use of empty space in Prizm

[nsg Profile]

Prizm battery compartment has 2 really huge empty spaces on the left and right of a battery box.
I tried to fit 1" long mini USB cable there, but, sadly, it is just a little bit too wide to fit into any of them.
So, for now I cut 1/2" strip off of an old credit card and placed it there. I use this strip to pry out batteries.
It is ideal battery removal tool. Nonconductive, non-scratchy.

[gbl08ma Profile Website]

It really looks like an huge space but it's not. I already looked into fitting there some kind of memory capacity expansion thing which would communicate through the 3-pin port. That space seems huge but nothing really useful fits in it - except your battery removal tool (I think fingernails are enough...)

[nsg Profile]

Here is what i mean.

usb device on the left is a flash drive, it is there just show the fit. The usb connector fits in the top part of the compartment just right. Unfortunately, premade cables have some fat plastic cases around the connector. But i believe that with bare connector, and some ribbon cable i can make a cable that will fit there.
(and on the right you can see my battery removal tool. I envy the toughness and length of your nails)

[helder7]

I tested connecting a lamp to a battery AAA and it lit:

We can use this space to have "Neons" on calculator (tuning) perhaps with colored LEDs and a switch (to save battery).

About the usb cable, will be difficult (but not impossible) put in this space.
I have a small cable USB <-> MicroUSB. It does not fit in space but if I cut the plastic on the left and right (2mm + 2mm), it possibly will fit. However I do not need.

[Casimo Profile]

Awesome!
I want a prizm.

[cfxm Profile]

[removed]

[Casimo Profile]

No, I want a small calc with neons

[Arkhs Profile]

Hi!
I'm thinking about trying to put an external SD card reader in my Prizm. I found the board MMC Project.
The problem is it needs an information input with the HIGH 3,3V and the calc only sends 2,8V. and the output of the MMC is also 3,3V and sure the calc needs only 2,8V.

Any tips?

[SimonLothar]

I'm thinking about trying to put an external SD card reader in my Prizm. I found the board MMC Project.
The problem is it needs an information input with the HIGH 3,3V and the calc only sends 2,8V. and the output of the MMC is also 3,3V and sure the calc needs only 2,8V.

Any tips?

Do you want to use a MMC-board with the serial interface? (in this case you would need a serial adapter cable to convert the calc's serial TTL-signal to RS232). That would be a bit bulky.
Or do you want to bypass the MAX233 and connect the calculators serial lines directly to the PIC?
Or do you mean that there might be a problem with the MMC-board-power supply?

[Arkhs Profile]

I was thinking about removing the db9 connector and soldering a 3pin female (connected to Rx, Tx and Gnd).

A person has done something similar to this idea for older casio calculators. (demo1 and demo2).

I want copy and backup content in school, without using a computer. I'm afraid to spend money on this board and it does not work, because it needs 3,3V (and it is also very large).

Perfect would be get a board that fits inside the calculator and expand the original 16 mb.

Anyway yesterday I had an idea after seeing a video on youtube. Some android phones have the USB OTG feature (some bring it natively disabled). I do not know if mine has or not but I'll try to find out. Maybe I'll have to put a Cyanogenmod and purchase a special cable.