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A series of measurements of
A# ./ubb-patgen -f 41kHz 1
A# ./ubb-patgen -f 41kHz -c
B# ./ubb-la -f 12 -n 10
yielded these results:
1 3 gap 2 0 1 3
------- ------- ------- ------- ------- ------- -------
106 77 11 98
120 78 11 83
134 79 11 68
3 79 11 53
18 78 11 39
33 78 11 24
47 79 11 9
62 79 5 6 140 147
77 79 11 125 147
Where for example the last entry corresponds to
...1{146}3{77}
0{11}1{125}3{147}...
Since this looks as if DAT1 was 1 for 77 samples before the first capture
ended, was 0 throughout the pulling low of DAT0 (11 cycles), stayed low
for another 125 cycles, and then went high for the 146.29 nominal
half-period, we thus get a gap length of 2*146-77-11-125 = 79
Ben Blinkenlights ================= This is an umbrella project for various items related to using the 8:10 card slot of the Ben Nanonote. The "flagship" sub-project is no longer the top-level LED board but the Universal Breakout Board, in ubb/ . The original blinkenlights, a board with a line of LEDs cam/ Outline of the board; obsolete ext/ UBB variant with ground between signals; obsolete ioscript/ GPIO test pattern generator; experimental libubb/ Helper functions for accessing UBB lpc111x-isp/ In-system programmer for NXP LPC111x MCUs nxuart/ Card with ATmega48 in UART configuration; incomplete swuart-chat/ Software-implemented UART (on UBB) ubb-jtag/ JTAG via UBB (example for Milkymist One) ubb-usb/ Design for hypothetical UBB-based USB host ubb-vga/ VGA output using UBB and minimal circuitry ubbctl/ Set and query UBB signals from the command line ubb/ The Universal Breakout Board (UBB) 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.