So my latest weird thing to teardown is a Military Biblestick, by Faith Comes By Hearing, a non-profit organization.
It's an audio device that plays the bible. Well, part of it. The New Testament and some of Psalms.
And here's the device itself. Quite small, only 5 buttons.
3.5mm audio port on the end, and a battery compartment for a AAA on the back.
(Along with the text "IBSM A/A2 1901" )
Opening it up reveals it's one PCB, with 5 switches on the PCB, two LEDs, a big chip, and a microSD card slot
The other side has another chip, an oscillator, and some assorted passives.
So the u2 chip on the back is a Winbond 25Q32JVS1Q: a 4 megabyte SPI flash chip.
The big chip on the front is an Actions ATJ3315D-X: a "third generation single-chip highly integrated digital music system solution for devices dedicating to audio players etc"
Basically it's an MP3-player-on-a-chip.
It's got about 36 kilobytes of built in RAM, 17 kilobytes of ROM for firmware, power regulation to run off a AAA battery or similar, and it can do USB, SD, memory stick, Smart Media, and MMC out of the box. it's also got a stereo DAC and headphone driver for audio output, and a mono ADC for recording audio.
two fun things about this chip:
1. It's not actually an MP3 player, I was wrong: it's a WMA player!
2. it's not an 8051... it's a Z80!
@foone not quite the same Z80 as from the Sinclair Spectrum tho?
@falken yeah, no. It's a much more powerful chip that simply uses a Z80 core for some programmability.