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  1. I am trying that dot matrix display now/ Results seem promising. It uses SPI too. I do all of my access to the Analog Shield in a timer1-driven interrupt routine. I have been doing the display interface in the non-interrupt code. That display access is slow, but slow is acceptable.... I found the interrupt and non-interrupt use of SPI could interfere with each other. I used the Arduino SPI.usingInterrupt() function as described in https://www.arduino.cc/en/Reference/SPIusingInterrupt and even better in http://dorkbotpdx.org/blog/paul/spi_transactions_in_arduino I made further progress. #include <SPI.h> .... SPI.usingInterrupt(255); This cured the display anomalies. The 255 is special in that you don't have to figure out what they want as an interrupt number.
  2. To follow up, I have tried each Uno port output pin D0...D13. Only D1 works to output my signal. Many make the display stop working or even hang the development environment. I fee confident that D1 will not interfere with the Analog Shield, since the schematic shows P7-2 on the Analog shield is not connected. I am going to try an Adafruit 1947 touchscreen display. That will free up pins. I hope it doesn't take a lot of memory for the library or accessing code. Also, on the 2-row connectors that mate with the Analog Shield, I have gone to a better pattern. If anybody is interested, I would be glad to post that.
  3. Why would that be? Is the differential read just slow, or is there a bug?
  4. I am working slowly on my project. I thought I might post what could be a useful DipTrace base layout for a shield to use with the Analog Shield on an Arduino Uno . It could even be useful to somebody making an unrelated shield for Uno by stripping out the P1, P2, and P3 headers on the left and adjusting the board outline. The component designations and pin numbers match those of the Analog Shield. My board may end up bigger than the Analog shield, but I have put a board outline into the file that matches the 2.1 by 3.1 inch dimensions of the Analog Shield. I think it is correct, but I have not had a board built. I made a copy of my in-progress layout, and stripped out the components. The Analog Shield uses Uno D2,D3, D5, D6 (P7-3,4,6,7) for its data to or from the Uno. As an aside, on my specific project, I have a Sainsmart 2x16 LCD Keypad-Shield that will go atop my custom shield. As far as I can tell, that uses Arduino signals D4,D5,D6,D7,D8,D9 and AD0. The Uno uses D13 for its LED, but could be shared in a pinch. That would seem to leave me with Uno D0, D1, D11, D12 to use for my own use by my shield. I expect to only need 1 or 2 Uno output port pins to my exclusive use. Any opinions as to which is/are most likely to be available, even if I upgrade to a different display shield in the future? Attached PDF is expanded scale. Bluish-gray is bottom silk. Green is top silk. Blue lines are ratlines for some of the grounds, and may be ignored. 1. I hope the DipTrace layout is useful to somebody. 2. Suggestions are encouraged. Analog_Shield_Base.dip img_ Analog_Shield_Base.pdf
  5. Confession: Part of original post was: "Using Uno board with an Analog Shield. What fixed resources does the Analog Shield library use? I have code that stopped interrupts from occuring by doing only #include <analogShield.h> , but the interrupts resumed after commenting out the include. This code was to establish a timed interrupt for accessing the Analog Shield, and I did not get to integrating in my analog access stuff." Well, my problem was really stupid. I had a call to the lcd inside an ISR. Duh.
  6. It will ultimately be carried into and then out of a vehicle. I will be able to supply cigarette lighter circuit power, and I expect to regulate that down to maybe 8 or 10 volts to let let the on-board regulators not have to work too hard. The use in the vehicle would be about a couple hours at a time. Yes, I will want the display facing up or at least out. I may tinker at time. I am hoping that most later tinkering will be with software. But I think the header stacking connectors would be reasonable for access and suitable for vibration. I have ordered an received some cute little terminal blocks . 5 connections each, on 0.1 centers. Top screw to pinch down on side wire. The boards above the special interface board will have to be removed to give screw access to attach or detach wires. I am thinking this will maybe be good for the occasional rewiring. I might hook that to a connector harness, or I might bolt my stack of boards to a radio (that most of the external wires go into) and carry the assembly as a big chunk. I can see building more open and then enclosing after things are working. I have had small circuit boards made before for a 1 or 2 unit build like this will be. But building with a pre-perf board with prototyping solder pads/holes might be sufficient. Thanks.
  7. The D2A and A2D connections are on 4x2 headers. Does somebody know a good way to access those signals onto a prototyping shield? My stack of boards will have a display on top. My first thought was a low profile plug that would bring out wires to the side. I could then run those wires to a separate driver to give more current out. I guess I could make my own shield by solder some long tail connectors onto generic 0.1 inch spacing. Those connectors seem to be called tall stackable connectors. I don't need to pass the 3x2 pins that are not on 0.1 centers. Suggestions are welcome. This is for hobby use. Edit: I am now thinking of using an oversized prototyping board with tall connectors soldered in. The Arduino Uno would be on the bottom. The Analog Shield would be next up. The big proto board would be next. The display would be on top. I would put the stack into a case with the big proto board being the mechanical connection to the case, and the other things being above and below. I could and insulating spacers to keep vibration from letting the pieces from coming apart. Still looking for ideas. I don't need a lot of space for my custom circuitry. Maybe a couple 14 pin dips and some passive components. And maybe some solder-on screw terminals or some other connectors for wires going out.
  8. Diagonal

    Analog Shield

    ‚ÄčI tried using a Mega2560. I confirm that it does not work with my simple ramp program I modified from an example. That program works with the Uno. I had been looking forward to having more memory. Thanks.