XO Stick

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Revision as of 20:11, 24 July 2012 by CScott (talk | contribs) (Programming)
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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