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  1. personally I use the SPI method exclusively for the smart LEDs (WS2812B, and sk6812 recently) one trick for getting the timing to cooperate is to set the SPI divider to get you close then you can change the rate of the MCLK registers to fine tune the timing. it only has to be changed while the SPI is transmitting so you can change the clock back to normal "speed" after your done with the transmission.
  2. well i decided to try and do a switching converter for the power on my board because i figured it is what I neede (LDO in reality would have been cheaper / easier, live and learn) the chip i designed the circuit for was the TPS62177 fixed output 3.3v regulator... all good and well but well the PDF datasheet is shared between that and the TPS62175 which is the adjustable version... well needless to say the 62175 was what got ordered. and an adjustable regulator in a fixed circuit umm well blows a hole in the chip, quite a spark erupting from it as well. not the best image but its ha
  3. hey guys I decided to cut down a launchpad to send just the programmer piece to a customer to load a program into a product with. and i was getting annoyed that the cutboard refused to talk to or download to a processor, while a full launchpad worked just fine. I knew you could cut the board at the dotted line, so i was frustrated. after some research it turns out the communication trace going to the RST (and maybe the TST) one as well actually is routed down between the two rows of pins on the 10 pin jtag header between the two sides of the launchpad board... if you follow the dotted l
  4. Barq's root beer... (hehe i never could get into the taste of beer, too bitter for me
  5. unfortunately i have to detect 16 different lines (these are output verification on a relay control module, so i gotta do 15 copies of this circuit, and don't have the room to implement alot of these suggestions.) the msp430 talks to an open drain constant current led driver, driving the LEDs inside some SSR relays to switch the AC signal to control the 120v relays on the target piece of equipment) each of these outputs is what I am sensing and feeding into the sensing optocouplers, all acting as open drains on on a common sensing bus, so when i put it through self test, it turns each on
  6. that is something to say towards the opto then, because worst case is the capacitor would fail shorted and would cause the optos LEDs to blow and wouldn't take out anything else cause the output side is still isolated.
  7. the power for this is coming from a 840KW 4160V generator, so power is pretty much unlimited, my primary concerns are isolation, footprint, cost, and excessive heat dissipation. I like that sensor chip, but at 3.75 a piece they will get expensive, and sensing current would require the relay at the far end to be working. the second concern is the need for 15 copies of this on the board and those SOT8's will take up too much space i think. Thanks for the suggestion, I may use those for a different function i need though in studying the charts in the datasheet, I only have to overcome
  8. I posted this on a different forum and got some help but wanted to run it past you guys to see if anyother ideas shook out of the tree. [this is a repost from a different forum combining a few of my posts] hey guys the project I am working on requires me to sense the presence of 120v on 15 different lines back to my microcontroller, trying to do it with optocouplers means i have to drop 120v across resistors to provide 20mA to the opto LED means i am dissipating 2.5W on 15 different resistor sets... 30W in a relatively small plastic box is gonna get very hot. there has to be a simple way
  9. well the processor can and will sit paitently by and wait for the next clock, this is how the debugger on the launchpad works anyway, it counts the clock cycles and when it stops the clocks at a given clock then it knows where the target processor is in its cycle.(i think) so you can in theory feed as few or as many "clocks" in as you need and the logic state machine will faithfully step forward as slow as you want, just realize how many tens or hundreds of clocks it can take to perform a given function (which you don't notice at MHZ speeds, but if you were at say 10 clocks / second would
  10. The earth ground is commected to the groundame of the pcb in the same place it was in the metal case (where the pcb mount holes are, i wired those 4 points together and connected the earth wire. That is also the common output line for the dc Sent from my iPhone using Tapatalk
  11. well I needed a full 24v supply to test my project here (only 300 mA) and i thought hey i can snag the 12V and -12V rail from my workhorse ATX supply i have, but then i thought this morning, HEY i got that Dangerous prototypes ATX breakout board as a prize on the forum here a while back although at this point i don't remember for what. so i was off to the races, resoldering and reworking the dc half of the ATX supply board to clean up the wan-hung lo construction and massive blobs of solder all over everything... anyway it now only has a single line from each rail to the pin on the b
  12. I need to send an updated program to a customer to load. but I don't want to send the c++ files and CCS. I know I can compile to a binary file, how can i get the customer to download this file to the msp? I can provide the loader circuit from the launchpad, but what program do they use and whatnot, I have never had to load a program other than from the c++ inside CCS
  13. thanks for the fast reply pabigot. string.h was already included for other stuff, so bonus. if ( strncmp(Line,"[start config]",lineLength-2 ) == 0) works beautifully for me.
  14. hey guys working on reading a config file and parsing it. so i read some number of bytes into a buffer (64 byte long) is there an easier way to test is the bytes read match a given string. currently I have to do this *read bytes* if (Line[0] == '[' && Line[1] == 's' && Line[2] == 't' && Line[3] == 'a' && Line[4] == 'r' && Line[5] == 't' && Line[6] == ' ' && Line[7] == 'c' && Line[8] == 'o' && Line[9] == 'n' && Line[10] == 'f' && Line[11]
  15. what usb are you using, is it the software bitbang USB code we wrote here or some hardware solution. how is your pcb laid out what pins of the debugger are you hooking up to, just the test reset lines, or all 6 (tst, rst, vcc, gnd, txd, rxd). does the chip "run" without the debugger and the usb just doesn't enumerate, or does it not run at all? many questions, need answers [edit] hehe and I posted that before reading the rest of the thread, but several are still valid questions [/edit] I know bbusb is sensitive to the clock frequency playing nice, maybe the debugger is messin
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