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Product SEN-10266 | about a year ago

Bug report: The post above was formatted exactly as I wanted when I hit “Preview”. When I actually posted it it took out all the carriage returns. Also, I couldn’t get bulleted lists to work even in preview.

Product SEN-10266 | about a year ago

Can you point us to some documentation of the output format when used with the Keychain IR Remote?

After digging through some forum posts I found this description:

“The whole set is 13 pulses long. The pulses are only measured while low. The first pulse, the start pulse, lasts about 2.4 ms (2400 microseconds). The following pulses are 1.2 ms (1200 microseconds) for a 1, 0.6 ms (600 microseconds) for a 0. Each data pulse is about 0.3 ms (300 microseconds) apart. Every set of 13 pulses is about 20-30 ms apart from each other, repeating when a button is held down.”

This is helpful, but it’d be nice to see it officially documented somewhere.

It seems like using one of these with an Arduino would be very difficult if you want to do more than just decode the IR signal. You have to poll pretty quick to reliably catch the 2.4 ms start pulse.

Using interrupts would work better, but you have to be careful. Libraries like NewSoftSerial will disable interrupts for the entire transmission or reception of a byte. At 9600 baud thats > 1 ms, so good luck catching pin change interrupts that are only .3ms apart. Even at 57600 baud you’ll have the same problem.

Blocking interrupts for the entire reception of an IR key (max 1.5ms*13 + 2.4 ms = 21.9 ms) isn’t a good idea either.

In my case, I’d like to use this IR receiver on an Arduino that also has a Serial LCD attached via NewSoftSerial. It just seems quite difficult to do. I donno, maybe I’m missing something.

Product BOB-08745 | about 3 years ago

Why not just make a breakout board for the TI TXB0108 and/or TXS0108E? 8 Bidirectional level shifting lines, and the chips are only $2 each.

Product SEN-00758 | about 3 years ago

If the standalone chip is available for $15.95, why is the breakout board so (relatively) expensive at $43.95. The other breakout boards don’t seem to have such a high markup over the chip price.

Product DEV-09063 | about 3 years ago

Any word on when this will be back in stock?

Product SEN-08193 | about 3 years ago

The Gyro datasheet listed should really be changed to the ADXRS401. Its a bit confusing to link to a datasheet with a different max rate.
Also, how easy is it to tap into the analog signals from each of the sensors? My project involves hooking this up to an Arduino, but the serial port is already tied up with something else (an XBee module).