@CamilStaps LC is a very strange area indeed. How it works is pretty amazing. But most of the particulars are top secret. At one place I worked at it was so secret that our LC chemists actually didn't know the formulation of the LC itself. They just ordered from three different places and mixed it themselves. So definitive answers will be hard to come by.
@jippie You are an experimentalist. Sometimes testing takes more effort, and more error prone. For instance right now I can't for the life of me get the clock divider to work as expected.
@Kortuk One time I tasted a beautiful vintage 400V 150mA adjustable supply. It had a nice pop with a general mouth feel of lightly cooked meat and copper. The nose on the supply was an exotic warm dusty phenolic with hints of overheated carbon composition resistors. I would rate it 97/100
@jippie Experimentally determined: SPI clock is fed by the raw oscillator. Instane. Your CPI is running at 150Khz, but it is sending SPI at 10Mhz. I'll send you logic analyzer logs, if you'd like.
user61389
Ah, the good ol' times I wasn't aware of SE and just did my homework. Anyway, I'm out as well for a few minutes.
@jippie I am running of 20Mhz crystal (I need all the speed I can get).
@jippie It is still possible that I did something very wrong, but I am looking at a logic analyzer trace where the clock signal is out on CLKO pin of the ATmega, and the SPI clock is running in circles around the mcu clock :)
@jippie I thought one of the points of MCU clock prescaler is so that you can use clocks above 20mhz, divide it inside the mcu and not be in the "do you feel lucky?" region...
@angelatlarge I believe so. Test it. This is true of several different families of MCU. The rationale is, you can run MCU slow to save power, yet timers should run as best they can.
@angelatlarge Bus pirate timing drifts by several percentage, invariably drifting in one direction, I forget which - largely because of processing overheads causing missed interrupts.
Apparently I misread the datasheet: on CLKPS: "This feature should be used if the selected clock source has a higher frequency than the maximum frequency of the device at the present operating conditions"
@AnindoGhosh Yeah, several percentage points would be nice.
I'm to the task to design a BJT Common-Emitter Amplifier with resistance at the emitter as in the figure, and for that I need to:
get the values for \$R_{1}\$, \$R_{2}\$, \$R_{C}\$ and \$R_{E}\$
given \$I_{CQ} = 3\text{mA}\$ , \$V_{CEQ} = 6.5\text{V}\$ ,\$V_{CC}=13\text{V}\$ and \$\beta = 380\...
Yeah, I only need to interrupt the regular routines to load the data from the register into main memory, right? What happens if in the mean time new serial data arrives, I mean, before I read the received data register?
Have to study the datasheet tomorrow I guess. Too tired now.
That "i know that input impedance in an amplifier is kept as high as possible to reduce the effects of this phenomenon" comment exasperated me. Sounds like certain arrogant older gentlemen I hear of. "I know" as a basis for a hypothesis.
Vineet Kaushik, the Loading Effects question. I notice that some of the worst attitudes, and the most poorly formulated questions and comments are by my countrymen (and women). This is embarrassing.
AVR SPI only works on 8-bit data. I need to send 12-bit data. As I am shuffling nibbles into bytes, I end with an extra nibble, which shifts everything out of place.
@Jaigus I would say about half to three quarters of the people here do, or occasionally do, embedded work in its various flavors - from actual semiconductor design, to FPGA / CPLD work, to microcontrollers, to full SoC systems. Skills span the range from semiconductor optics and chemistry, through theoretical and applied physics, to advanced high-level software skills. I hope this helps.
@Jaigus Speaking of EE being broad, you will also find a wealth of analog electronics wisdom here, even including obsolete (I prefer the term legacy) technologies. However most of the time, all you will find here is a bunch of old-timers (e.g. me) pulling the leg of some youngster (e.g. them).
@angelatlarge I strongly believe there is something you are doing wrong in this entire business - a hybrid of hardware SPI and bit bashed SPI in the same data stream rings all the alarm bells for me. There must be something obvious you are missing.
While this question is not within the norms for this site, it is one frequently asked, so here is an outline, take it where you will:
It would behoove you to get a couple of books to gather a preliminary understanding of electronic design in general, e.g.
Practical Electronics for Inventors, ...
Basically I cut the copper at the hole on two parallel strips. That gives me 4 copper conduction strips for the 4 leads. Then, the upper two partial strips, I solder-jumper them to the next parallel rows. So at the bottom, I have 4 stripboard strips, ready for the header pins for a 4-pin SIP module for breadboard.
I'm to the task to design a BJT Common-Emitter Amplifier with resistance at the emitter as in the figure, and for that I need to:
get the values for \$R_{1}\$, \$R_{2}\$, \$R_{C}\$ and \$R_{E}\$
given \$I_{CQ} = 3\text{mA}\$ , \$V_{CEQ} = 6.5\text{V}\$ ,\$V_{CC}=13\text{V}\$ and \$\beta = 380\...
While this question is not within the norms for this site, it is one frequently asked, so here is an outline, take it where you will:
It would behoove you to get a couple of books to gather a preliminary understanding of electronic design in general, e.g.
Practical Electronics for Inventors, ...
