NHD-2.8-25664UCB2 goes dark under heavy updates

[peter]

I am using the NHD-2.8-25664UCB2 as the main user feedback during the satellite antenna pointing exercise.  The user needs to know where the antenna should point (azimuth and elevation), where it is currently pointing, and what the current receive signal strength might be.  The updates to three of these items can happen 7 times per second.

I am using:
•   Adafruit library
•   SPI 4 wire interface
•   TS-4600 SBC (https://www.embeddedarm.com/products/TS-4600)

The OLED will go blank (black with no text) or it will freeze after an unspecified amount of time.  The underlying application is still running, we know this through the debian linux OS and with an oscilloscope checking the SCLK, SDIN, DC, CS signals on the display.

The display buffer is cleared before every write to the display, and only one display update can be performed at a time.
I have other configuration / information screens that are accessed through a keypad.  Any of those screen images will display for hours, even days without any issues.

[Paul_B]

Morning Peter,

I’m sorry to hear about the trouble you are having with the NHD-2.8-25664UCB2. I feel these are software related issues on your end. Can you please provide the library link and attach your initial setup sequence?

Finally, for trouble shooting purposes can you provide me with a detailed pin-out diagram so I can verify your connections?

Hope this helps, feel free to contact me if you have any questions or concerns 

[peter]

Hello Paul,

If you provide an email address I can send you the our entire library along with schematics.

I access the library via TCL

proc initialize_display {} {
   global textSize
   # 12.5MHz
   oled begin 12500000 1
    
        oled set_text_size $textSize
}

#####################################################################
#
# Used for pointing the dish at the satellite.  Shows target satellite,
# current position, and RSSI (Receive Signal Strength Indicator)
#
# This screen can not be "SELECTED", there isn't anything for the user to
# accomplish except move the antenna by hand.
#
#####################################################################
proc satellite_tuning_screen { userdata } {
   # display size 64 X 256

   global highlightTitle
   global target_elevation
   global target_azimuth
   
   if { ![get_var printingToDisplay] } {
      debug "printing to display [get_var printingToDisplay]"
      set_var printingToDisplay 1
      
         
       if { ![get_var in_satellite_tuning_screen] } {
                set_screen_selection_false
                set_var in_satellite_tuning_screen "true"
       }
       
            oled clear_display_buffer

            oled set_text_size 1

            print_text_location 80 0 "Elevation"
            print_text_location 150 0 "Azimuth"
         
            print_text_location 10 16 "Target"
            print_text_location 80 16  [get_var target_elevation]
            print_text_location 150 16 [get_var target_azimuth]
   
            print_text_location 10 32 "Current"
            print_text_location 80 32  [get_var compass_elevation]
            print_text_location 150 32 [get_var compass_azimuth]

            print_text_location 10 48 "RSSI"
            print_text_location 60 48 [get_var rssi]

            oled display
   
       set_var printingToDisplay 0

   } else {
      debug "Display update was stoped becaus another display update was in progress!!!!"
   }
   
   
}

[Michael_L]

Hi Peter,

Please use our technical support email nhtech@newhavendisplay.com to send any relevant documents/files.
You may reference Paul/this forum post in your email, and we will be more than happy to provide any help needed to get your display fully functional.

Thanks!

[Paul_B]

Morning Peter,

The maximum frequency depends on the slave device in this case the NHD-2.8-25664UCB2. After reviewing the SSD1322 datasheet the max clock speed is 10MHz, you will need to lower the clock speed so you are not in violation of the datasheet.

1 / (100ns) = 10MHz