linux lcd display quotation
If you like collecting quotations like I do, then this instructable is for you. This instructable will show you how to put together a way to display your quotes for all to see, using things you probably already have around the house.
Any kind of quote will do, but because the picture frame scrolls through the images that will contain the quotes it works best if you keep the quotes short. Longer quotes, although interesting, may not remain on screen long enough to be read. If you have a number of longer quotations, see "Some Final Notes" at the end of this instructable for tips that you can consider for longer display times.
Look at the sample images stored on your LCD picture frame. For my frame, all of the sample images were 856x480 pixels. To determine this, right click on the image file, and select Properties. You should see a number of tabs, one of which should be called “Details.” Click on the details tab; under Image you should see a width and height. Write this down or keep the window open, because we will use it to set up PowerPoint.
Take the smaller of the two numbers (usually the height), and divide that by the larger number. In my case, 480/856=0.5607. Checking the table below (which shows common screen image ratios), I can see that the native images on my LCD picture frame are just about in 16:9 format.
Open PowerPoint, and start a new presentation. On the ribbon, click Design, Page Setup. In the setup dialog box, select the image format that matches the native format of your LCD picture frame. We do this because it helps prevent the software driving the frame from cropping or stretching the images unnecessarily. Click Home on the ribbon.
At this point, your presentation should have two slides: The initial default title slide, and your newly inserted blank slide. Click on the first slide (the title slide), click your right mouse button, and select delete. You should be left with a single blank slide in your presentation, sized to the native image size of your LCD picture frame.
In many cases, the picture won’t fill the slide because it’s in a different format than the native format for the LCD picture frame. Thus, we’ll need to resize the image to fit. At the same time, we don’t want to distort the image either. Here’s the most straightforward approach:
4. My LCD picture frame doesn’t let you change the display time for pictures, and some of the transitions happen too quickly to allow you to read the entire quote. You can do what I did, which was to make two copies of every slide. PowerPoint is creative in its naming; the slides are called Slide1.jpg, Slide2.jpg, et cetera. I named my copies Slide1a.jpg, Slide2a.jpg. The file system sorts the original and the copy together when the files are named this way, so every quote is displayed twice with an intervening transition.
5. If you don’t have a lot slides suitable for quotes, consider visiting a site like Interface Lift, which has a wide range of images in a variety of formats for desktop wallpapers. Chances are, you’ll be able to find images in a format suitable for the native format of your LCD picture frame.
On a Mac, there"s a relatively easy compose shortcut, but I couldn"t find a shortcut for Linux. There doesn"t even seem to be a compose key combination, based on https://help.ubuntu.com/community/GtkComposeTable
It wasn’t planned to support a refresh rate sufficient for video streaming. The AT91SAM9G45 contains quite a workable built-in LCD controller with DMA support and a fairly high speed data bus, which could potentially achieve a speed sufficient for video playback, but alas, it is not hardware compatible with the SSD1963 controller. Therefore, it was decided to use an ordinary GPIO interface for this purpose, as the only available alternative.
This display uses 888 pixel format . It means that : 8 bytes are used for Red, 8 bytes – for Green, 8 bytes – for Blue. Quite frequently one can found displays with 555 , 565 and other pixel formats, but that’s not our case. Format of transmitted data is shown in Figure 2 .
As you know, the Linux kernel provides interfaces for different types of device drivers – char drivers, block drivers, usb drivers, etc. Framebuffer drivers are also the separate subsystem in Linux device driver model. The main structure, which is used to represent the FB driver is struct fb_info in linux / fb.h. By the way, this header file could also be interesting to fans of humor in Linux kernel code, since it contains an interesting definition:
I think, the definition speaks for itself . But, moving back to the structure fb_info. Two structures there are of particular interest – fb_var_screeninfo and fb_fix_screeninfo. Let’s initialize those structures with parameters of our display.
As for any other Linux kernel module, we need the init/remove function pair. Let’s start with init. Framebuffer drivers are usually registered as platform_driver:
Liquid crystal display (LCD) is a flat panel display that uses the light modulating properties of liquid crystals. Liquid crystals do not produce light directly, instead using a backlight or reflector to produce images in colour or monochrome.
In our AM3354 based custom designed board, I want to control the LCD back-light manually through command line, once the board is up. Currently, in .dts file the LCD back-light pin is assigned to a PWM pin. Please help me to achieve this.
The Canadian mechanical engineering student hacked the dashboard display screen in his car, so it’s now displaying funny quotes from Reddit. Specifically, it’s displaying those weird “Shower Thoughts” — the headlines from Reddit’s forum for the brilliant one-off insights that pop into your head at random moments.
Luckily, all the digital devices in his 2012 Hyundai Genesis Coupe were connected using a fairly common standard — the “Controller Area Network bus” (or CAN bus). So Harin grabbed one of his Arduino’s — plus a cheap SPI CANBUS circuit board — and just started doing some experiments. When he first installed his Arduino circuit board into the dashboard, the LCD began showing the time of day — every ten milliseconds — and any new messages that he sent to the screen were simply being wiped out when the system re-transmitted. But Harin had already built up a strong motivation to keep moving forward, according to a recent write-up in Make: magazine, because “I hated that stupid little blue LCD. It would just sit there staring at me brightly with the words ‘AUX’…”
So he re-routed the LCD’s input. And fortunately, Harin’s other Raspberry Pi board could accommodate a WiFi dongle. By using an iPhone for connectivity, it was now able to draw down the funny Reddit quotes. And Make: also reported that his next project may be to install a router directly into his car.
Harin’s even mounted his Nexus 7 Android tablet into his car’s dashboard and is using it to play music. In the comments on his blog, he talks about one day transmitting the “now playing” information from the tablet to the LCD. Somewhere in the mix, there’s even an SQL database. “My main script retrieves the top post from Shower Thoughts and converts the characters to their hexadecimal equivalents, adds the message ID and row identifier, and stores it in an SQL database.”
There’re two more scripts just for retrieving the quote from the database and display it on the screen, which Harin says will be building blocks for more features down the road. “Eventually, I’ll be able to screen the messages intended for the LCD on the primary [CAN bus] network and add the ones I want to keep to the SQL database while removing the ones I don’t need anymore.”
Now instead of seeing the external temperature on his display, he sees bits of mind-blowing amateur philosophy. But maybe it goes to show you that if you’re going someplace strange, your journey there can be just as unpredictable. According to his blog post, the screen was originally intended for displaying song information (title and artist) for Sirius XM.
The Canadian mechanical engineering student hacked the dashboard display screen in his car, so it’s now displaying funny quotes from Reddit. Specifically, it’s displaying those weird “Shower Thoughts” — the headlines from Reddit’s forum for the brilliant one-off insights that pop into your head at random moments.
Luckily, all the digital devices in his 2012 Hyundai Genesis Coupe were connected using a fairly common standard — the “Controller Area Network bus” (or CAN bus). So Harin grabbed one of his Arduino’s — plus a cheap SPI CANBUS circuit board — and just started doing some experiments. When he first installed his Arduino circuit board into the dashboard, the LCD began showing the time of day — every ten milliseconds — and any new messages that he sent to the screen were simply being wiped out when the system re-transmitted. But Harin had already built up a strong motivation to keep moving forward, according to a recent write-up in Make: magazine, because “I hated that stupid little blue LCD. It would just sit there staring at me brightly with the words ‘AUX’…”
So he re-routed the LCD’s input. And fortunately, Harin’s other Raspberry Pi board could accommodate a WiFi dongle. By using an iPhone for connectivity, it was now able to draw down the funny Reddit quotes. And Make: also reported that his next project may be to install a router directly into his car.
Harin’s even mounted his Nexus 7 Android tablet into his car’s dashboard and is using it to play music. In the comments on his blog, he talks about one day transmitting the “now playing” information from the tablet to the LCD. Somewhere in the mix, there’s even an SQL database. “My main script retrieves the top post from Shower Thoughts and converts the characters to their hexadecimal equivalents, adds the message ID and row identifier, and stores it in an SQL database.”
There’re two more scripts just for retrieving the quote from the database and display it on the screen, which Harin says will be building blocks for more features down the road. “Eventually, I’ll be able to screen the messages intended for the LCD on the primary [CAN bus] network and add the ones I want to keep to the SQL database while removing the ones I don’t need anymore.”
Now instead of seeing the external temperature on his display, he sees bits of mind-blowing amateur philosophy. But maybe it goes to show you that if you’re going someplace strange, your journey there can be just as unpredictable. According to his blog post, the screen was originally intended for displaying song information (title and artist) for Sirius XM.
is the simplest file transfer protocol to exchange files to and from a remote computer or network. Similar to Windows, Linux and UNIX operating systems also have built-in command-line prompts that can be used as FTP clients to make an FTP connection. Here’s a list of commonly used
Spatial uniformity of displayed luminance can vary widely between different makes and models of LCD, the major determinant of uniformity being the backlight scheme [34] (some older LCDs allowed VGA input and relied on built-in analog-to-digital conversion, also a potential source of noise). Two commonplace schemes are, first, direct backlighting, wherein a spatial array of light-emitting diodes (LEDs) and a diffuser screen sit behind the liquid crystal panel, and, second, edge illumination, wherein light emitted by a linear array of diodes at one of the display’s edges is spatially distributed via lightguide. We quantified the spatial uniformity of the CG247X by presenting low-, medium-, and high-luminance static test patches at nine display positions (Fig 2, inset) and using the LS-110 spot meter to measure the luminance of each patch. At each luminance tested, we calculated the grand average over all display positions, and divisively normalized measurements by that average. As illustrated in Fig 2, at medium- and high-luminance, the CG247X showed greater spatial uniformity than our consumer-grade LCD (Dell U2415b): for the CG247X, spatial variation was 5.1% at medium and 3.5% at high luminance, whereas for the U2415b, variation was 8.1% at medium and 8.5% at high luminance. The uniformity of the two displays was comparable at low luminance (CG247X, 27% versus U2415b, 17%). Prior to normalization, there were, as expected, marked differences between low-, medium-, and high-luminance measurements. For example, at display position 5 (Fig 2, inset) on the CG247X, low-luminance measurements ranged from 0.07 to 0.10 cd/m2, medium-luminance measurements ranged from 57.70 to 57.93 cd/m2, and high-luminance measurements ranged from 113.9 to 114.2 cd/m2 (Table 1). We also quantified spatial surround effects; using a tripod at 1 m, we measured displayed luminance at position 5 comparing large (1920-by-1200 pixels) and small (384-by-384 pixels) 100%-luminance patches. For CG247X, the mean of 10 large-patch measurements was 0.56 cd/m2 greater than that of 10 small-patch measurements (two-sample t-test, p < 0.01), i.e., an increase of 0.50%. For the U2415b, the increase was 0.71 cd/m2, i.e., 0.67% (two-sample t-test, p < 0.01).
In-plane switching (IPS) LCDs, like our CG247X and U2415b, enable larger viewing angles than older LCD technology (e.g., twisted-nematic displays) [23]. To do so, IPS displays interdigitate electrodes (see 23]. For the displays we tested, vendor-issued specifications state a viewing angle of 178 deg, however, in the absence of further details, that derived measure is difficult to assimilate. We measured displayed luminance as a function of viewing angle over a range of azimuth and elevation (±60 deg). We fit a circular von Mises function (Fig 3, the CG247X and U2415b performed comparably in this regard. For the CG247X, the FW90M was 28.6 deg (fitted parameters: α = 1.45, κ = 3.37) and 32.6 deg (α = 1.65, κ = 2.62) for azimuth and elevation, respectively. For the U2415b, the FW90M was 31.2 deg (α = 1.60, κ = 2.85) and 31.0 deg (α = 1.55, κ = 2.90) for azimuth and elevation, respectively. At high-luminance we made a reduced set of measurements, assuming rotational symmetry, varying azimuth or elevation from 0 to 60 deg. These additional measurements yielded similar FW90M estimates. This descriptive model can be used to select a viewing distance with tolerable attenuation due to viewing angle. For example, if the CG247X is viewed from 1 m, a stimulus presented at the top of the display’s vertical meridian (i.e., elevation = 9.2 deg) would, due to viewing angle, undergo luminance attenuation by a factor of 0.97.
We presented a large, static test patch, measuring luminance with the LS-110 spot meter near the display’s center. We used a turntable to rotate the display (
A common misconception among vision researchers and clinicians is that LCDs do not flicker (i.e., that LCDs are temporally uniform). In fact, there are two major sources of flicker that can affect a LCD: first, backlight flicker which usually occurs at temporal frequencies (e.g., 1000 Hz) well beyond the critical flicker fusion frequency (e.g., Elze & Tanner [24], and Ghodrati, Morris, & Price [35]), and, second, the so-called frame response which occurs at the refresh rate of the display (here, 60 Hz) [23, 36]. Frame responses are largely attributable to an LCD’s inversion scheme: a feature of modern displays wherein the polarity of the video signal voltage applied to the liquid crystal material is inverted from one video frame to the next. This inversion minimises long-term degradation, or aging, of the display by minimizing the DC voltage across the liquid crystal elements. Frame inversion schemes typically have fine spatial structure, on the scale of individual pixels, making them mostly imperceptible (e.g., dot inversion schemes [36]). We quantified the temporal uniformity of the CG247X by presenting (nominally) static test patches at display position 5 (Fig 2, inset) and using the linearized photodiode device to measure displayed luminance over time. At each of 11 luminances (0, 10, 20 … 100%) we made 10 one-second recordings, averaging the Fourier amplitude spectra of those 10 recordings. Fig 4 shows the average spectrum at each luminance. The spectra of the CG247X revealed a frame response comprising a 60 Hz component as well as harmonic components at integer multiples of 60 Hz. The response at 60 Hz varied non-monotonically in amplitude with the luminance of the static test patch, peaking at a luminance of 50%. However, the CG247X appeared free of backlight modulations. This absence of backlight modulations freed us of the consequences of said modulations (often desynchronized with the frame refresh signal) on increment/decrement transitions between luminances (see Fig 5 in [24]). The spectra of our consumer-grade LCD also revealed a frame response, as well as 1.2 kHz flicker, likely associated with the back light. This latter temporal nonuniformity increased linearly with the luminance of the static test patch.
We presented nominally static test patches at display position 5 (Fig 2, inset), measuring luminance with a linearized photodiode device. At each luminance (0, 10, 20 … 100%) we made ten 1-second recordings, deriving the Fourier amplitude spectrum for each. Each spectrum illustrated is the average of 10 spectra. For each display, we normalized spectra such that 1000 corresponds to the DC component at 50% luminance; therefore, a value of 5.0 corresponds to approximately 0.15 cd/m2. The spectra of the CG247X (upper) revealed a frame response, comprising a 60 Hz component and harmonic components at integer multiples of 60 Hz. This frame response varied non-monotonically in amplitude with the luminance of the static test patch, peaking between 40 and 50% luminance. The spectra of the U2415b (lower) also revealed a frame response, as well as 1.2 kHz flicker, the amplitude of which increased linearly with the luminance of the static test patch (amplitudes above 5.0 are not shown, arrowheads). For the U2415b, mains noise (50 Hz) was apparent at high-luminance. lum., luminance.
For each display, we verified that the frame response was optical and not related to any radiated electromagnetic noise: We used the oscilloscope to visualize the Fourier amplitude spectrum online. We then interposed opaque cardboard between the photodiode and display which caused the disappearance of the frame response. For the U2415b, we similarly verified that the 1.2 kHz response was optical.
In general, LCD response times—the duration of the rise or fall of a step from one luminance level to another—vary as a function of both step source and destination luminance. This nonlinear behaviour is owing largely to mechanisms of response time compensation (RTC) (e.g., the work of McCartney [25]), a feature of many modern LCDs designed to enhance video. RTC mechanisms speed luminance transitions by transiently altering the voltage applied to the liquid crystal associated with individual pixels (e.g., Fig 1 in [27]; Fig 5 in [24]). We measured the CG247X’s response times by presenting luminance steps—both increments and decrements—to the linearized photodiode device. Step source and destination took values 0, 25, 50, 75, or 100%. As illustrated in Fig 5, response times varied as a function of both luminance step source and destination. For example, stepping from 0% luminance to 25% luminance took 24.5 ms, stepping from 75% to 100% took 12.9 ms, and stepping from 25% to 0% took 8.1 ms. All of these steps are the same height, but response times differ markedly. Overall, the response times of our consumer-grade LCD were less than the CG247X response times. However, as we will illustrate below, faster is not better; although RTC mechanisms reduced the response times of our consumer-grade LCD, they contaminated displayed luminance with overshoot and undershoot artifacts which are problematic for many applications in clinical and experimental vision research, including the presentation of mean-modulated flicker. RTC mechanisms lower “black-white-black” and “grey-to-grey” response times, which are used to promote displays to the gaming community and other consumer markets.
(A) CG247X response times. The leftmost gray box (labelled “0%”) encompasses four points showing mean response times for transitions from source luminance = 0% to destination luminances = 25, 50, 75, and 100% (x axis). These rise times (upward triangles) decreased with increasing destination luminance. The gray box labelled “25%” shows mean response times of transitions from source luminance = 25% to destination luminances = 0, 50, 75, and 100%. The fall time (downward triangle), from 25% to 0% luminance, was less than the rise times. Overall, response times varied as a function of both source and destination luminance, as is generally expected of LCDs. We made 10 measurements at each source/destination luminance pair; error bars, where not obscured by symbols, mark the full range (from minimum to maximum) of these 10 measurements. (B) U2415b response times. Graphical conventions are as in A. Overall, U2415b response times were less than CG247X response times.
At the outset of this study, we made preliminary measurements similar to those illustrated in Fig 5. We noticed that rise and fall times straddling 50% luminance were approximately equal (e.g., rise time from 25% to 75% = 16.3 ms; fall time from 75% to 25% = 17.1 ms) which led us to wonder whether the CG247X could be used to display achromatic, mean-modulated flicker without the introduction of unworkable artifacts. To better determine the CG247X’s potential suitability for presenting mean-modulated flicker, and its susceptibility, or otherwise, to overshoot and undershoot artifacts typical of LCDs implementing RTC mechanisms, we presented mean-modulated flicker on both the CG247X and our consumer-grade display, using the linearized photodiode device to measure luminance over time. We used a flicker period of 20 frames (333.3 ms), and contrast ranging from 20 to 100%. As illustrated in Fig 6, the consumer-grade display’s luminance traces revealed overshoot and undershoot artifacts symptomatic of RTC. The CG247X’s luminance traces, however, appeared free of RTC artifacts. We used these traces to estimate response times specific to mean-modulated flicker, illustrated in Fig 7. Overall, CG247X rise and fall times were greater than those of our consumer-grade LCD. However, with the exception of 100% contrast, CG247X rise and fall times were approximately equal, indicating its potential suitability for presenting mean-modulated flicker.
Flicker period = 20 frames (333.3 ms), and contrast = 20 to 100% in increments of 20 as marked. At 40% contrast, the arrowheads show examples of luminance step source and destination as used in the computation of response times (Fig 7). For each display, we normalized traces to the luminance step destination at 100% contrast. For the U2415b, over- and undershoot are readily apparent at low and moderate contrast. The CG247X, however, shows exponential rise and fall, regardless of contrast.
To further determine whether the CG247X could be used to display achromatic, mean-modulated flicker without the introduction of unworkable artifacts, we presented flicker at frequencies ranging from 0.94 to 30 Hz and contrasts ranging from 20 to 100%. We used recorded traces (similar to those in Fig 6) to derive cycle-averaged luminance. In Fig 8, we illustrate how cycle-averaged luminance was approximately constant for all flicker frequencies, and for contrasts up to 80%. At 100% contrast, cycle-averaged luminance decreased with flicker frequency, indicating that, at full contrast, the monitor is not suitable for presenting mean-modulated flicker. Cycle-averaged luminance recorded from our consumer-grade LCD (Dell U2415b) varied as a function of flicker frequency at all contrasts tested; this variation is problematic for presenting achromatic, mean-modulated flicker. We also used CG247X traces to derive cycle-averaged r.m.s. luminance. In Fig 8, we illustrate how cycle-averaged r.m.s. luminance decreased with flicker frequency, indicative of loss of contrast. The consumer-grade LCD was affected by both changes in cycle-averaged luminance and loss of contrast.
We presented mean-modulated flicker at a range of flicker frequencies (0.94 to 30 Hz) and contrasts (20 to 100%). We used waveforms (e.g., Fig 6) recorded from the CG247X (A) to derive cycle-averaged luminance; we divisively normalized that derived measure using the cycle-averaged luminance of a “reference” waveform, that is, the response to contrast = 20% and flicker frequency = 0.94 Hz. This relatively low-contrast, low-frequency waveform was chosen as reference because it should be easily realized by both displays. For clarity, cycle-averaged responses for contrast = 40, 60, 80, and 100% are offset by -0.1, -0.2, -0.3, and -0.4 log units, respectively (arrowheads). As shown, cycle-averaged luminance was approximately constant for contrast = 20 to 80% at all flicker frequencies tested (0.94 to 30 Hz). At contrast = 100%, cycle-averaged luminance decreased with flicker frequency. Cycle-averaged luminance recorded from the consumer-grade U2415b (B) increased with flicker frequency at all contrasts tested. Graphical conventions are as in A. We used waveforms recorded from the CG247X (C) to derive cycle-averaged r.m.s. luminance; we divisively normalized that derived measure using cycle-averaged r.m.s. luminance of the reference waveform (20%, 0.94 Hz). As shown, at all contrasts tested (20 to 100%), cycle-averaged r.m.s. luminance decreased with flicker frequency, indicative of a loss of effective contrast. Cycle-averaged r.m.s. luminance recorded from the U2415b (D) revealed both increases and decreases to effective contrast with flicker frequency. Each symbol is the average of 10 measurements. (None of the data in panels C and D is offset.) We modeled cycle-average luminance and r.m.s. luminance on the CG247X as a causal exponential decay (Methods). This model comprised one free parameter, τ. For the illustrated fit (blue), τ = 6.6 ms. The red symbols in panel C (slightly offset rightward for clarity) show the result of a validation experiment (see
Taken together, Fig 8, and the traces used to derive the measures plotted there, indicated a simple relationship between nominal and displayed luminance on the CG247X, namely, that the latter was, simply, a low-pass-filtered version of the former. To test this hypothesis, we modeled the function transferring nominal luminance to displayed luminance as a causal, exponential decay (Methods). We optimized the single free parameter in this model, the time constant of the exponential decay (τ), by minimizing the sum of the squared error between the model-derived cycle-averaged mean luminance and cycle-averaged r.m.s. luminance, and those derived from the photodiode traces. For the CG247X, the fit is illustrated in Fig 8 (blue). There, the fitted parameter, τ, was 6.6 ms. To assess the fit to cycle-averaged luminance, we computed the root-mean-square error (RMSE) separately at each flicker contrast. For the CG247X, the RMSE was negligibly small for contrasts from 20 to 80% (ranging from 6.0e-4 to 6.3e-3 normalized units). At 100% contrast, RMSE was highest at 0.093. This simple model was a poor fit to the U2415b, not illustrated in Fig 8. For the U2415b, RMSEs were high, ranging from 0.04 at 20% contrast to 0.15 at 60% contrast. To assess the fit to cycle-averaged r.m.s. luminance, we calculated the square of Pearson’s correlation coefficient, R2, separately at each flicker contrast. For the CG247X, R2 was high, ranging from 0.9965 to 0.9999. As expected, the same calculation for the U2415b was consistent with a poor fit; at its worst, R2 = 0.03.
To quantify the nonlinearities associated with high-contrast, mean-modulated flicker, and to quantify temporal dependence between frames, we used a paired-pulse paradigm [37, 38]. We presented paired biphasic luminance pulses at position 5 (Fig 2, inset), systematically varying the inter-pulse interval, T (Methods). We used the measured responses to individual pulses to predict paired-pulse responses, and to model the display’s nonlinearities we subtracted each paired-pulse response from its prediction. Fig 9 shows the nonlinear behaviour of the CG247X and, for comparison, that of our consumer-grade LCD. In our CG247X, a nonlinear mechanism appeared to speed the transition between white and black (100% and 0% luminance, respectively; leftmost upper panel in Fig 9B). When paired pulses were separated by 16.67 ms or more (the three rightmost upper panels in Fig 9B where predicted and displayed luminance are approximately equal), the CG247X behaved linearly, that is, we saw no evidence of temporal dependence between frames. In our consumer-grade LCD, a nonlinear mechanism appeared to attenuate the transition to white (100% luminance; leftmost lower panel in Fig 9B). This attenuation reconciles with Fig 6 (lower), which shows marked overshoot at moderate contrast (e.g., 60% contrast, middlemost panel of Fig 6), but a near absence of overshoot at high-contrast (rightmost panel of Fig 6). Compared to the CG247X, the U2415b’s nonlinearities were large in magnitude and long-lasting. Paired pulses separated by as much as 33.33 ms (the third lower panel in Fig 9B, where predicted and displayed luminance are unequal) evoked nonlinear behaviour in the U2415b, that is, we saw clear evidence of temporal dependence between frames.
(A) Illustration of the paired-pulse paradigm. We presented a single biphasic luminance pulse (e.g., left panel), parametrically varying its latency relative to a trigger (cf. left and middle panels). We then presented a pair of biphasic luminance pulses (right panel), parametrically varying the offset between pulses comprising the pair, T = 0, 1, 2, and 3 times the frame period (frame period = 16.67 ms). Single-pulse responses can be used to predict the paired-pulse response; differences between this prediction and the displayed luminance model the display’s nonlinearities. (B) Nonlinear behaviour of the CG247X (upper). The four panels show responses to paired pulses with various offsets, T; we normalized responses (0, 0.5 and 1 corresponded to 0, 50 and 100% luminance, respectively) and then subtracted the baseline. For each offset, the predicted displayed luminance derived from single-pulse responses is shown in blue, and the measured displayed luminance in response to paired pulses is shown in black. The measured responses are an average of 16 recordings. The difference, that is, the nonlinearity, is shown in red. For the CG247X, superposition (T = 0 ms) of pulses evoked a nonlinearity which accelerated the transition from 100% luminance to 0% luminance. There was negligible nonlinearity of displayed lumiance for T > = 16.67 ms. Compared to the CG247X’s nonlinearity, the U2415b’s nonlinearity (lower panels) was large in magnitude and long-lasting, affecting subsequent frames (to T = 33.33 ms). Graphical conventions are as in B.
There are only a few special characters involved in working with character strings on the command line or in a script on Linux: the single quote, the double quote and the backslash. But the rules aren’t as obvious as one might think. In this post, we’ll look at the easy and the somewhat tricky uses of these special characters.
Of course, the other thing that you can do is use a backslash character. This tells bash that you don’t want the apostrophe to be interpreted, but just displayed.$ echo Please don\’t each the daisies
Expand the remote-files on the remote machine and do a get for each file name thus produced. See glob for details on the file name expansion. Resulting file names are processed according to case, ntrans, and nmap settings. Files are transferred into the local working directory, which can be changed with ‘lcd directory’; new local directories can be created with ‘! mkdir directory’.
Toggle verbose mode. In verbose mode, all responses from the FTP server are displayed to the user. Also, if verbose is on, when a file transfer completes, statistics regarding the efficiency of the transfer are reported. By default, verbose is on.
Once at the ftp> prompt, you are placed in the default directory for the user you used to log in. The first thing you"d probably want to do is see what directory that is. To see the present working directory, use the pwd command like in Linux:
This produces a file listing, like in Linux. You can change remote directories with cd. If you want to change what directory you"re using on your local computer, you can use lcd for "local change directory." Let"s say you want to get a file from the server named awesome.jpg, and download it to your local directory /home/myuser/images:
This directory had a "README" message that is displayed by the FTP server every time you change it to your current directory. The server then lets you know the cd command was successful. Now let"s download every JPEG file using a wildcard. We can use the mget command, which allows us to get multiple files with one command:
reset
additional device support.watchdogThese commands allow a user to view and change the current state of the watchdog timer.getShow current Watchdog Timer settings and countdown state.resetReset the Watchdog Timer to its most recent state and restart the countdown timer.offTurn off a currently running Watchdog countdown timer.selftestCheck on the basic health of the BMC by executing the Get Self Test results command and report the results.getenablesDisplays a list of the currently enabled options for the BMC.setenables
authcap
info [channel number]Displays information about the selected channel. If no channel is given it will display information about the currently used channel.
Configure user access information on the given channel for the given userid.getciphers
statusDisplays information regarding the high-level status of the system chassis and main power subsystem.pohThis command will return the Power-On Hours counter.identify
Number of AMC bays supported by Carrier: 2power
match (default)
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*unmatch
{state} = one or more of the following:online | present | hotspare | identify | rebuilding | fault | predict | critical | failedlcdset {mode}|{lcdqualifier}|{errordisplay}
Allows you to set the vKVM status to active or inactive. When it is active and session is in progress, a message appears on LCD.lcd statusDisplays the LCD status for vKVM display active or inactive and Front Panel access mode (viewandmodify, view-only or disabled).setled
macDisplays the information about the system NICs.mac listDisplays the NIC MAC address and status of all NICs. It also displays the DRAC/iDRAC MAC address.mac get
with failover lom2,shared with failover lom3,shared with failover lom4,shared with Failover all loms,shared with Failover None).lan get activeReturns the current active NIC (dedicated, LOM1, LOM2, LOM3 or LOM4).powermonitorDisplays power tracking statistics.powermonitor clear cumulativepowerReset cumulative power reading.powermonitor clear peakpowerReset peak power reading.powermonitor powerconsumption
Protocol Vendor ID : 7154print [
get
entity
the ipmitool command line. This can greatly improve performance over system interface or remote LAN.fill sensorsCreate the SDR Repository for the current configuration. Will perform a "Clear SDR Repository" command so be careful.fill file
invoking the sel time get and sel time set
system interface.
of the format of this file.writeraw
getDisplays the SEL clock"s current time.set
info [
the currently used channel.payload
summaryDisplays a summary of userid information, including maximum number of userids, the number of enabled users, and the number of fixed names defined.listDisplays a list of user information for all defined userids.set
is present in all modern 2.4 and all 2.6 kernels and it should be present in recent Linux distribution kernels. There are also IPMI driver kernel patches for
work:ipmi_msghandlerIncoming and outgoing message handler for IPMI interfaces.ipmi_kcs_drvAn IPMI Keyboard Controler Style (KCS) interface driver for the message handler.ipmi_devintfLinux character device interface for the message handler.
Ms.Josey 
Ms.Josey