From 759daff979cbe4cd356aab92a705e716559ccb0d Mon Sep 17 00:00:00 2001 From: Werner Almesberger Date: Wed, 1 Sep 2010 04:26:31 -0300 Subject: [PATCH] Describe origin and purpose. - README: describe the project's origin and purpose - bbl/bbl.c: corrected title --- README | 15 +++++++++++++++ bbl/bbl.c | 2 +- 2 files changed, 16 insertions(+), 1 deletion(-) create mode 100644 README diff --git a/README b/README new file mode 100644 index 0000000..8232086 --- /dev/null +++ b/README @@ -0,0 +1,15 @@ +Ben Blinkenlights +================= + +This project is a proof of concept implementation of Rikard Lindstrom's +idea of using the Ben's uSD 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 uSD 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. diff --git a/bbl/bbl.c b/bbl/bbl.c index f081655..36bbaad 100644 --- a/bbl/bbl.c +++ b/bbl/bbl.c @@ -1,5 +1,5 @@ /* - * bbl.c - Read or write any CPU register + * bbl.c - Produce a "Knight Rider" effect on the LED board * * Written 2010 by Werner Almesberger *