Post Created date
Multiplexing serial RS-232
How do you handle the situation when you are talking to device 1 and device 2 sends data?
Friday, 28 April 2006 - 18:05
measurement of low voltage
Did you try Nuno's circuit or megaAVRfreak's modification? That should work well for a single supply circuit. Note that the feedback resistor needs to be pretty high, as in nuno's...
Friday, 28 April 2006 - 17:57
Multiplexing serial RS-232
I agree that mutiplexing serial lines is generally a bad idea. I tried it and it _sorta_ worked but was fraught with problems. MUXint the signals is the easy part but managing the...
Friday, 28 April 2006 - 02:51
avr-libc 1.4.4 released
I may have missed something in the News release, but it looks like the documentation for General Utilites has changed and is missing a section: (This is also posted on another...
Wednesday, 26 April 2006 - 00:17
Converting Floats to Strings?
Hey, I just checked the library reference here: and it is missing the float conversion utilities. I checked the cached version on google and...
Tuesday, 25 April 2006 - 23:51
Find/Post your Online C Books & Tools here ....
This one changed my programming life. I own maybe 6 of the books that are listed above and have been through a lot of tutorials and I have never been able to grok C but now at...
Tuesday, 25 April 2006 - 22:57
sending strings over USART
I ran across a project today that looks good. AVR SimpleUART - buffered/interrupt driven serial It is very similar to what is in my comms...
Tuesday, 25 April 2006 - 22:38
Using crystals on solderless breadboards
I use 8 and 16 MHz crystals without a problem. I do not think I would try anything much beyond 40MHz. And, yes, there will be some differences in performance between a solderless...
Tuesday, 25 April 2006 - 16:29
ADC and RMS calculation - reducing size of variable types
I did not see anone reference this app note on Atmel's site. I think this link will do it. Also look for the source code for AVR465. It is...
Tuesday, 28 March 2006 - 06:57
ac signal >> full wave bridge rectifier >> ADC
Here is a better schematic for a precision rectifier. It works very well. Note that rectifying the signal adds higher frequency content to the input ADC signal. Filtering the...
Wednesday, 4 January 2006 - 04:17
battery back up system
The transistors to isolate the voltage divider is good. The ORing diodes should be _after_ the regulator to improve useful battery capacity. There is no charger in this circuit.
Friday, 28 October 2005 - 18:30
Soldering Iron
Hakko and Metcal are great but pricey. I bought an Edsyn 951sx Loner (temperature controlled no readout) new for $79 a few years ago and it has been very good. It will not win any...
Tuesday, 25 October 2005 - 06:58