Of course they can still be bought, like Z88. Plug in the battery, flip on the switch and taps on.
Been thinking about doing something like this for a while, just for the fun of it. What it takes:
- keyboard, that can talk to:
- MCU
- decent display, mono, low power, no need for back light
- SD card, for data transfer
After digging around, there happens to be a blue tooth keyboard somewhere at home, after cracking it up, there is one NRF chip inside:
Nah... don't want to work with BT if I can help it. So, I just bought another cheap ass USB keyboard for almost nothing. And here is its guts:
There is already plenty of MCUs around for me to play with, but none of them have USB host capabilities, and this one is a USB keyboard.... But wait, on PCB it says PS2/USB, huh...
After some digging around, it turns out that this might just be a PS2 keyboard after all. It appears that some keyboards, like this one, may have a USB connector, but in fact, it's just a connector. For example inside a PS2 to USB connector:
If this is the case ( it probably is, for the price what can people expect ) then it would be much easier, for a USB host board is not only expensive and hard to find around here.
And there is some serious sounding PS2 library : PS2KeyAdvanced. Of course I have to test the keyboard myself, probably under some logic analyzer, because I have a feeling that this keyboard might have a much higher CLK speed than what a cheap 8 bit AVR MCU can handle.
As for display, I want something that is big, preferably something like this:
I really love something bigger, without back light, yet cheaper and easier to find. One good thing about those LCDs is that they need little RAM to work with, I just need to use command mode and save some RAM for SD card interface and such.
Last thing is the case. Hacking together all above is not hard, what is hard for me is the casing. Ideally, the casing should be part of the keyboard itself. I just need to make some modifications and such. But in order to keep things small and portable, there is no such space on a small keyboard.
There WILL be some serious casing modification going on.
