Member Since: December 25, 2008

Country: United States

  • Is this a 1m strip?

  • What is the range of this PCB antenna combined with the SM130 module and various Sparkfun 13.56MHz tags? Since the transparent tag is bigger, I'd expect it to be readable from (slightly) farther away, but I'm not sure if that means 2 inches or 12 inches.
    Has anyone found a cheap way to read a relatively small (dog-tag size) passive RFID tag from about 3 feet away?

  • I have the same issue. When powering the mic with a 5V supply, ADC readings from an Arduino are always at or near 866 (4.2V). I can get some dynamic range (ADC readings 331-670) when powering it from the 3.3V supply. I have not messed with voltage dividers or AREF yet. If someone could post a schematic for getting a sound intensity from whisper to shouting for these to cover the full range of the ADC on an ATmega328p it'd be much appreciated.

  • The data sheet clearly says that the center pin is 2.0mm in diameter. Barrel jack dimensions are confusing.

  • From the ATmega168 data sheet: "The ATmega48, ATmega88 and ATmega168 differ only in memory sizes, boot loader support, and interrupt vector sizes." So nevermind about the schematic.
    I guess I might be able to speak FT245RL (parallel FIFO) to the board from my uC. A PITA, but at least it's easier than writing a usb host driver.

  • The schematic for this references an ATmega48, but on my board I have an ATmega168 20AU. Is there an updated schematic available?
    Would it be possible to patch into the uC's RX/TX pins directly, bypassing the FT245RL and making this product easily useful with a generic microcontroller that does not implement USB host mode?
    I realize there is an SPI version, but I have sunk $50 into this USB version and would still like to use it with a uC (without implementing USB host mode).

  • The slowest the 16 MHz Arduino hardware SPI can go is 125KHz (16MHz / 128). You could figure out how to clock it differently or use an 8MHz Arduino, with the SPI clock / 128 = 62.5 KHz, maybe this is close enough. To set the divider to 128, set bits 0 and 1 of the SPCR register (SPR1 and SPR0) to 1.
    I wish these things could do faster SPI. I'm hopeful that since ryowens84 has updated the LED matrix backpack for faster SPI, that this hardware (and software!) will get some love soon.

  • The Schematic only has 2 pages in it while the lower-right corner indicates that there are 3 pages.

  • This board uses a USB interface with one of those FTDI USB chips (like how an Arduino does USB), so when you plug it into your computer (after making your own cable or soldering the 4-pin JST connector to a female USB socket), the computer uses the FTDI driver to present your OS with a serial port. On my XP system it shows up as COM33. You can set the baud rate for this port via the Windows XP Device Manager -- right-click the port and choose "Properties." Mine was set to 9600 8-N-1 by default.
    Does anyone know if it's possible to speak serial directly to this board without going through the FTDI USB chip?