How to drive VFD matrix tube?

Other Hardware Displays
1

I've a VFD matrix tube I try to get some images out of. It is lighting up, it shows garbage (random pixels), so voltage and stuff is OK. The driver IC is a NEC D65012 with a bunch of NEC D16304's behind it (can't find anything on those IC's)
I use an Arduino MEGA, as it has 5V logic.
Port A is connected to the address pins 0-7 for the columns, Port B is connected to the horizontal segments of 8 pixels high, Port C is the data port carrying 8 bits for each 1 pixel wide 8 pixel high part.
Pin 49 is connected to CLR
Pin 48 is connected to Disp EN
Pin 47 is connected to \RDY
Pin 46 is connected to \WR
I did try a lot of variations of the code below: first RDY high, then LOW, First LOW then HIGH, Disp EN high, then LOW, other way around, different orders. But nothing gives output.
There is no datasheet.

#define WR  46
#define RDY 47 // RS
#define ENA 48
#define CLR 49
#define DELAY 1
void setup() {
  DDRA=255;
  DDRB=255;
  DDRC=255;
  DDRL=255;
  digitalWrite(WR,0);
}

void loop() {
  for (byte b=0;b<8;b++){
    for (byte a=0;a<255;a++){
      PORTA=a;
      PORTB=b;
      PORTC=113;
      digitalWrite(RDY,1);
      delayMicroseconds(DELAY);
      digitalWrite(ENA,1);
      delayMicroseconds(DELAY);
      digitalWrite(ENA,0);
     delayMicroseconds(DELAY);
     digitalWrite(RDY,0);
     delayMicroseconds(DELAY);
    }
  }
  delayMicroseconds(100);
}

Who knows how to use these CLR, Disp EN, WR and RDY pins?

2

I remember that part from the early 1990's. My suggestion is to just get a new display along with current data and drivers. It will save you weeks of frustration. The display requires a negative voltage, some of them were in the mid 30 volt range.

3

Turned out to be rather simple. Just put ENA once to high at boot, then a short pulse on WR after setting the port bits. RDY is a return signal and a pulse on CLS clears the thing.
This display has all the voltage stuff taken care off. It is just GND,5V and 12V, where I make the 12V with a boost converter from the 5V.

4

Good going! I had no clue as to the display interface as you only mentioned parts and did not include a schematic.

5

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