XO Stick

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Assembly notes

- LEDs are polarized, flat side should be down (towards big USB port) - Zener diodes are polarized, make the black stripe match the stripe on the board

Programming

AVR Stick firmware will work unmodified (for the ATtiny85 version): http://www.sparkfun.com/products/9147

Sample programming command:

avrdude -c usbtiny -pattiny85 -U flash:w:main.hex  -U hfuse:w:0xdd:m -U lfuse:w:0xe1:m

Or "make fuse program" from the AVR Stick source distribution.

Do this as root if you need to (then go fix your udev by adding something like the following as /etc/udev/rules.d/10-usbtiny.rules

SUBSYSTEM!="usb|usb_device", GOTO="usbtiny_rules_end"
ACTION!="add", GOTO="usbtiny_rules_end"

ATTRS{idVendor}=="1781", ATTRS{idProduct}=="0c9f", MODE="0664", GROUP="plugdev"

LABEL="usbtiny_rules_end"

Would be nice to eventually have an assembly guide as detailed as the one for http://www.sparkfun.com/products/10547

C. Scott's other notes

Notes on v5:

- ATtiny261A should be at least ATtiny461a if not ATtiny861a, since USB library takes up 2496 bytes.

- full size USB convert to mini or micro? (no through-hole micro-B connectors?)

- LED1/LED2 need better polarity mark (flat side is down, towards big usb port)

- use '-kit' suffixed versions of footprints (solder mask on component side)

- break off tab appears to work well.

- island between tabs should be anchored to body, not tabs?

- can we avoid anchors on break off tabs, instead use central anchor?

  ie.
    T
 ------------
|            |
 --          \--
TXT|            |
 --          \--
|            |
 ------------
    T
where T indicates tabs.

- remove symmetry from USB connector placement to allow two tabs on XOrduino board. (ie, move connector all the way down)

Distribution

1. cjb
2. cjb
3. Steve Pomeroy
4. Quozl
5. Mike Lee
6. Pippin Wallace
7. Pippin Wallace
8. Sridhar Dhanapalan
9. Tony Forster
10. Javier Andres Galaz Jeria
11. Alan Jhonn Aguiar Schwyn
12. Stephen Thomas
13. Ricardo Moran
14. George Hunt
15. Juan Cubillo
19. cscott (no pcb)

Sources

http://github.com/cscott/xostick -- look at the "A1" tag for the schematics for the A1 boards. Latest XO Stick is at HEAD, targetted for the B1 build.

See also

XOrduino

Links

http://www.sparkfun.com/datasheets/Widgets/AVR-Stick-v12.pdf indicative circuit diagram http://arduino.cc/en/Tutorial/ArduinoISP programming the bootloader with another Arduino https://www.sparkfun.com/products/9825 pocket programmer http://www.atmel.com/Images/doc2586.pdf datasheet Attiny85 (the 8 pin chip) http://www.atmel.com/Images/doc2588.pdf datasheet Attiny861 (the 20 pin chip) https://github.com/cscott/xostick circuit board artwork, drill table and notes