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January 24, 2012
Product SEN-09695 |
about 2 months ago
So, starting from the code in github (https://github.com/sparkfun/MPR121_Capacitive_Touch_Breakout/tree/master/Firmware/MPR121Q/Arduino%20Sketch) I’ve been building an easier to use library for my personal use (I’ll probably submit it at some point). I’ve read through some of the MPR121’s datasheet, and want to try reading some direct register values from the chip, however its not clear to me how to do that using the Arduino Wire library. Anyone have pointers on how to do that?
Product COM-11694 |
about 9 months ago
Thanks for the info on the 4A cold start, I’ll make sure to design this project to handle that. I’m actually running this off a deep cycle battery and auto alternator, which means it’ll be getting up to 14.5V if I don’t also regulate it. Do you have any idea if the slightly higher voltage will damage them? Its my guess that it’d be fine as I’m betting these things are mostly used for lighting RV furnaces rather than household ones (most home furnaces I’ve seen use 120VAC ignitors).
Also - warning to the original poster and any one else: If you’re making plans to use one of these to ignite any kind of flammable fuel, especially if its pressured, be sure that you really know what you’re doing when it comes to the plumbing. Standard household natural gas is a pretty low pressure (probably 10-12PSI) whereas a fuel tank of propane can be 300PSI depending on the temperature.
Yeah, I don’t know about how long it takes to hit the maximum temperature, but I just replaced the 120VAC ignitor I was using on a flame effect prototype with this and it seems to take ~5 seconds to ignition.
Correct me if I’m wrong, but the Beefcake is overkill for this. I had a project a year ago running a number of 120V ignitors with a ~1A draw off one of those 8x5A120V relay boards. I’m currently building a flame effects project that will involve a number of these ignitors & 24V solenoid valves, and if I’ve done my math right these should be able to be driven by a TIP120 circuit. The datasheet claims a max of 2.4A@12.85V, so 30W (or 48W if your 4A claim is correct). The TIP120 claims a max of 65W so it should be able to handle this load, especially as these heat up rapidly and the draw goes down.
(Note: I haven’t actually got to the point of wiring this together, I’m currently running the prototype off one of the relay boards from the previous project. Regardless, a relay would still be fine, you can just use a much cheaper option than the Beefcake, with its 20A 240V theoretical maximum)
Product WRL-10421 |
about 2 years ago
Actually, never mind. Apparently one of my non-Pro XBees is somehow faulty. I pulled out a few unused ones and now have it working properly. The faulty Xbee will connext only with the other non-Pros, but the remainder connect to the Pro’s without difficulty.
I just ordered two of these (firmware XBP24BSE, model XBP24-B27WIT-004-revE) with the expectation that they were compatible with the non-Pro XB’s I have (firmware XB24-ZB, model XB24-Z7WIT-004-revD1). While I’m able to get the Pro’s to communicate with each other in AT mode, nothing I seem to be able to do will get the non-Pros to talk to the Pro’s. I was under the impression that these should work, was I incorrect or am I doing something wrong with them?