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Blinkenlights, Demonstrate the use of the uSD slot for DIY hardware http://projects.qi-hardware.com/index.php/p/ben-blinkenlights/
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Werner Almesberger 8bd7199d9e ubb-vga.c: removed commented-out code from earlier experiments
The history of the split prefetch code:

Once up on a time, I thought that it was important to stay very close
to the "official" pixel clock. We could do this when copying 32 bit
words from cache to the GPIO set/clear registers, but not when
shifting 8 bit values as we do now.

One problem with 32 bit values is that transferring that amount of
data exceeds the time available in the hsync pulse. Hence the idea
to split the prefetch between hsync pulse and horizontal front porch.

Note that we also split prefetches between the two VGA lines of each
QVGA line. This commit does not change that mechanism.

- ubb-vga.c (line, frame): removed code fragments for prefetch split
  between hsync pulse and front porch
- ubb-vga.c (line, frame): remove code fragments for measuring time
  relative to the rising edge of hsync (and letting the prefetch time
  control the hsync length), not the falling edge
2011-04-24 11:48:32 -03:00
avrdude avrdude/: fixed confusing typo in avrdude.conf, added tuxbrain's nanonote_ICSP 2011-03-09 17:28:24 -03:00
bbl bbl.c (main): open /dev/mem with O_SYNC to disable caching 2011-01-03 18:31:38 -03:00
cam Initial commit. 2010-09-01 04:02:24 -03:00
components uart: the AVR requires nSS for slave mode 2011-01-31 21:35:45 -03:00
ext ext/: added uSD extender board (draft) 2010-11-02 12:17:20 -03:00
nxuart nxuart/fw/Makefile (prog): supply an 8 MHz clock while programming 2011-03-07 17:21:54 -03:00
ubb usb/cam/Makefile: added dependency in Makefile itself; local parameter update 2011-03-07 13:43:36 -03:00
ubb-vga ubb-vga.c: removed commented-out code from earlier experiments 2011-04-24 11:48:32 -03:00
bbl.brd bbl.brd: updated 8:10-CARD to update pad type 2011-01-18 16:08:00 -03:00
bbl.cmp use 8_10-card.fpd instead of usd-card.fpd 2011-01-17 12:42:49 -03:00
bbl.pro use 8_10-card.fpd instead of usd-card.fpd 2011-01-17 12:42:49 -03:00
bbl.sch use 8_10-card.fpd instead of usd-card.fpd 2011-01-17 12:42:49 -03:00
BOOKSHELF Added simple UART 8:10 card. 2011-01-31 19:02:50 -03:00
Makefile Added simple UART 8:10 card. 2011-01-31 19:02:50 -03:00
README README: changed "uSD" to "8:10 card" 2011-01-17 12:45:42 -03:00

Ben Blinkenlights
=================

This project is a proof of concept implementation of Rikard Lindstrom's
idea of using the Ben's 8:10 card slot as a general extension interface
also for devices that don't speak MMC or SD/SDIO. The application is a
simple LED circuit, as suggested by David Samblas.

The 8:10 card slot gives access to six GPIOs, a 3.3 V supply that can
be switched on and off by software, and ground. We use a simple form of
multiplexing to drive ten LEDs with this interface.

Note that one should only light one LED at a time. If multiple LEDs are
lit, they will share the current though the common resistor, and will
thus be less bright than a single LED.