Search results

Could you expand a bit? I thought this was a comparator? I've since updated by removing the pot completely and putting in a solid resistor. However, the falling edge of the square wave is wacko. It's been suggested to me to remove my clipping zeners (which I don't understand why I'd want to...

Last night I attempted to fix the oscillation by changing my resistor values in my Schmitt trigger. My R1 value is soldered in as 510 ohms. The R2 value was 115000 ohms. I was able to completely eliminate the rising oscillation by using a 2.2k resistor. I tried dozens of resistors and this...

I talked to an EE at work and he believes the hysteresis needs to be adjusted. I'm going to try a different resistor next to my pot and see if I can get a better result. The shaft RPM reading is direct. The roadspeed value in the code is used to calculate other values, but not vice versa...

Yet it doesn't work in real life. The teensy is unable to read that square wave apparently. Is there a different way I'm supposed to be filtering it? Should I debounce the wave? Why is half the wave filled in? Here is the op amp circuit I'm using to generate the square wave...

Setup and loop: //==================== //Variables //==================== //Pins const byte RoadspeedPin = 2; const byte Solenoid1Pin = 3; const byte Solenoid2Pin = 4; const byte Solenoid3Pin = 5; const byte BrakePin = A1; const byte ThrottlePin = A0; //Digital 20 - 3.3v...

Hello All, I'm attempting to read a sensor value with a digital pin on a Teensy 3.2. This sensor value is a Variable reluctance sensor in an automotive transmission. Here are the waveforms on my oscilloscope, both at once: https://i.imgur.com/YzvjOrI.jpg Here is the filtered square wave...

I was going to use software debouncing + setting an activation threshold once I determine if it's just bouncing or an actual special switch. My only concern is that the brake switch I've been able to locate is hot all the time and grounds when pressed, but is independent of the signal output...

The curiosity is that the brake switch is old school.. A 1990 Jeep Comanche. The switch looks to give a slight voltage if pressed very lightly, which continues to rise to a point as you press, until it's full on. Anywhere from 1V to 5V to 11V finally when on.

I have a bunch of Sharp optos, but if the switch is indeed variable, or I need to adjust the sensitivity, I won't be able to make any adjustments via an opto signal. Is there an analog equivalent?

Hello everyone, I'm currently working on a Teensy 3.2 vehicle transmission project. I'll narrow down my question to specifics. There is a brake switch that triggers when the brakes in the vehicle are pressed. This input is read by a wire that goes into the (old) transmission controller...

I'm going to try this when I get home tonight: http://overskill.alexshu.com/saving-loading-settings-on-sd-card-with-arduino/

I wanted to give an update. My new Teensy's won't arrive until today, but last week, I went to check the vehicle's fuel level by reading the ohms on the fuel sensor wire and received a strange reading. I decided to check the value with the vehicle engine on or on accessories and was unable to...

I understand. The V/DIV is a 5v to 3.3v step from a regulated TCU source. That's the only reason I used it.

Here is the schematic I based the power on. Taken from work engineering department: http://i.imgur.com/Loatn4F.jpg

I've purchased two Teensy 3.6 replacements. I'm going to hand test each 12v opto and voltage divider to see if there's potentially a short that's sending 12v to a pin. I really won't know if I also killed my RA8875 controllers or displays until I get the new teensys in.

http://imgur.com/a/aX5Y8 This album has some fluff, but it shows the circuit boards in pretty good detail. I don't have an exact schematic. It uses dual RA8875s on a Tristate buffer, along with the bucks I listed above. There is also a Sparkfun level shifter. The Teensy 3.6 is powered...

These are the regulators I'm currently using, FYI: R-78C3.3-1.0, and R-78C5.0-1.0 https://www.digikey.com/product-detail/en/recom-power/R-78C3.3-1.0/945-1394-5-ND/2652147 and https://www.digikey.com/product-detail/en/recom-power/R-78C5.0-1.0/945-1395-5-ND/2652148

Do you think I could just get something like this...

No luck on the reset. It seems to be completely dead. The USB port actually burned me when I touched it on the Teensy just after about 30 seconds of on time. What I don't understand is how this happened. I have what I thought was a very beefy power setup with the 24v regulators, plus the 15v...

Thanks for the reply! Great info! I use the 3.3v regulator to power dual 7 inch display screens. I'm hoping they have a 3.3v version of these too!

Hello all, I've been working on a project for about 5 months now that centers around a teensy 3.6. It's an automotive dashboard display. It reads pins via optoisolators and displays everything to dual RA8875 controllers. I have a bench PSU and test setup along with the following power...

I found the changes made in the RA8875 update: http://i.imgur.com/XnsJwqB.png I was able to resolve this issue by changing the following lines on my code: rowBuffer[col] = tft.Color565(sdbuffer[buffidx++], sdbuffer[buffidx++], sdbuffer[buffidx++]); to rowBuffer[col] =...

This is the only reference I can find to this issue. This user had to use an LCD image converter and store it as an array. I need to load the images from an SD card: https://github.com/sumotoy/RA8875/issues/91

Alright, I've discovered that I can run all the other examples available without having messed up colors, so I think that means I can rule out the actual RA8875 library. It would seem that specifically loading a 24 bit BMP image is causing the colors to be messed up. Is there something I...

Here is the code I'm using. I've tried swapping out utility files, etc. I've verified the color defines. This code compiles correctly on both library versions, but the font only works on 0.70+, and the colors are messed up: /* Grab bmp image from an sd card. It reads column by column and...

The source code for this is just the built in SD card example, except pointing to my BMP file on the Teensy 3.6. Anyone have any ideas?

Hello, I've been trying to get my Adafruit_RA8875 display working with custom fonts. I've managed to get the fonts working by updating to the latest RA8875 0.70 library. Unfortunately, the new library completely breaks all the colors. I'm assuming there is some setting I need to change in...

Hey KurtE, I played around a bit with your library a few months ago when I first got this. I think the tri-state buffer is the easiest way here. Adding to the thread, the blog post is here: https://www.dorkbotpdx.org/blog/paul/better_spi_bus_design_in_3_steps And another post by Paul which...

Thank you both for the replies! Paul, I believe I found a write up you did on this earlier. I'll search that and get started. It still seems relatively easy. Reading a bit more about the SPI interface and it looks like everything you said is accurate. I'd just need to set the independent...

Hello, Before I order a second screen, I'd like to get some input on this project. I currently have a single Adafruit RA8875 screen hooked up to a Teensy 3.6. this screen is responsible for displaying several basic sensor inputs, but the font and size has to be large enough for readability at...

Hello all, I've been successful in connecting an Adafruit RA8875 to a Teensy 3.6. I'm able to load bump maps and default examples just fine. I'm trying to create a custom font by following Sumotoy's instructions. The .H file generates and is placed in the correct folder, but I'm receiving...

Hello, Starting a graphics display project with the Teensy 3.6. I've successfully integrated the Adafruit RA8875 controller with the Teensy 3.6. I'm not entirely sure how to load graphics from a Teensy 3.6 SD card. All the information I'm finding appears to be for the teensy versions that do...

Hello all, I've been trying to get basic fonts working on the Adafruit RA8875 800x480 display. I can't seem to get the display working with any examples except the built in build test example from the Adafruit library. I've tried compiling and successfully uploading Sumotoy's RA8875 code, but...

My current solution to this is to order a new 7 inch display with an RA8875 controller, since I'll be wanting all available pins for inputs on this project.

I ended up using the built in USE_B_D_PORTS configuration. Once I hooked up all the pins, I defined my constructor line with my pins: UTFT myGLCD(SSD1963_800,3,4,9,10); I also attempted to figure out how to use the new hardware define header file by adding it to the UTFT.h file: #if...

Thank you!! Let me spend some time with this and report back.

Hello all! I am attempting to interface the following display with my Teensy 3.6: Link to datasheets and specs: http://www.sainsmart.com/sainsmart-7-7-inch-tft-lcd-480x800-arduino-due-mega2560-r3-raspberry-pi.html The backlight will be powered externally. I've tried copying the exact pinout...