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i wonder how the real time data from microcontroller (TMS320F28835) can be displayed on 7-segment. I can view the data(float or int data type) on expression window in code composer studio but i want to display that data on 7 segment(SND3360). Need help for this problem. Any refernece code or manual for this problem will be helpful.

Looking for reference code or technical manual.

무함마드
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  • Does this answer your question? [Printing the value of variables(floating or Uint) from the code on SND3360](https://stackoverflow.com/questions/74651464/printing-the-value-of-variablesfloating-or-uint-from-the-code-on-snd3360) – Elliot Alderson Dec 04 '22 at 13:27
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    Asking for "_Any reference code or manual for this problem will be helpful._" immediately places your question off-topic. Also it is both a hardware and a software issue; you have to define your hardware before a software solution can be presented. – Clifford Dec 04 '22 at 16:01
  • those are the values displayed using a kind of lookup table, I need to display real-time data coming from the microcontroller e.g the value of the speed and as we know it changes with the reference so I want to show whatever values are in the speed variable. – 무함마드 Dec 05 '22 at 05:19
  • It is not clear what your question is. Can you already display digits on the display? If so your question is then simply how to generate the digits, and nothing to do with driving the display. `ssprintf` perhaps? You really need to fix this question. – Clifford Dec 05 '22 at 13:21
  • yes, i can display any number or alphabet on the 7-segment. But my question is how to display control input or output variable values on the 7-segment as those are floating variables. – 무함마드 Dec 06 '22 at 01:57
  • @무함마드. As I have said, there is insufficient information in your question to provide a software answer. All the information you have provided in comments needs to be in the question. It seems that the question is simply about generating the digits and decimal point for display and nothing to do with the hardware since you apparently already have drivers for that. Your question should include details of the existing_software_ API and more specific about your needs. At the moment there is a huge an unreasonable gulf between what you want and what you have told us. – Clifford Dec 06 '22 at 07:55

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The SND3360 is a very basic 6 digit display with no controller/multiplexer. For each digit you must have all the common cathode digit pins normally high, then set the segment pins for one digit and pull its cathode low to illuminate the selected LEDs. You would after a short delay reset the cathode high, then repeat for the next digit. By cycling through each digit rapidly and regularly persistence of vision will give the impression that all 6 digits are displayed.

You need to do this in software in such a way that the digit refresh rate is not affected but other code running. One way of doing that is to update the display in a timer interrupt handler or a high priority RTOS thread.

A hardware solution (and therefore off-topic) is to use a BCD to 7-Segment display decoder (e.g. CD5411to drive the segment pins, in that case your MCU needs just 4 pins instead of 8 to define the digit, and then 6 lines to select the digit - you could further use a multiplexer (e.g. 74137) to select one of 6 digit pins using just three GPIO, so with the BCD decoder and output multiplexer, you can connect the display using just 7 GPIO rather than 14 driving it directly from MCU GPIO. It also simplifies the software.

Even simpler is to use a controller chip specifically designed to drive exactly this type of display. For example the STLED316S. That can be driven from a three-wire serial interface. The controller handles all the multiplexing and refresh for you.

Clifford
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  • i am using a voltage regulator (sn74lvcc3245a). The pins of (sn74lvcc3245a) A1..A8 are connected with xd8..xd15(data lines), DIR is connected with XW/R and OE is provided by the output of (sn74lvc08A) where the inputs to (sn74lvc08A) are given from 3-8 line decoder, whose input are address lines (XA15-XA17). the address for display is ( 238000 ~ 23FFFF). – 무함마드 Dec 05 '22 at 05:33
  • @무함마드 clearly there is much more to your hardware design than is suggested in your question. That information should be in the question, not in a comment. Ideally as a schematic or block diagram rather than text. If it is a COTS board, simply include a link. As explained above the the software required depends on the hardware. Currently your question lacks focus, it is unclear how you could end up with a hardware design without knowing how to drive it, so what _specific_ problem are you encountering? I am not sure the voltage regulator is at all relevant in this case. – Clifford Dec 05 '22 at 13:14
  • it's true that the voltage regulator is not relevant here and I just mentioned giving a view of the circuit. Actually, it's a customized commercial board and I don't have any reference link for the circuit. Furthermore, i just want to display the result of the control variables on the 7-segment. i want to read the value from their address and display them on 7-segment. – 무함마드 Dec 06 '22 at 02:30