I've dabbled with Arduino on and off for years, I can see its seriously powerful but it's always way over my head, I can solder, repair electronics, rewire a house if I need to, but when it gets down to coding and understanding schematics I really struggle - my brain just doesn't seem to work in a way that can understand it.
That being said I have an old display from a device I'm trying to repurpose, it has 3 DLG3416 modules on it, a few caps, a resistor, 2 MC14094B shift registers which presumably are going from serial to parallel maybe?
The connector on the board is a 7 pin connector and has the following pins:
5V, Data 1, Clock, Data 2, Blank, 5V (again?) and GND
There are actually no schematics for that board it was obviously 'a secret' from the manufacture.
If I connect up 5V, GND to the Arduino I do get some random characters on the displays before they turn off. That's as far as I've got.
I've found:
Both links look interesting but I just don't even really know where to start. Can anyone help?
The best suggestion is to buy a new I2C communicating display.
Identifying the LCD itself but not knowing the board likely cost a lot of time and efforts.
I have other displays (new) that I've successfully interfaced with from Arduino, but I specifically need to connect to this display as it fits in a specific enclosure etc etc.
I have googled that as you suggest - I should of added the link to the original post, that shows how to interface with one of those display modules directly, but not with the specific shift register.
I should imagine someone a lot more smart that I could connect an Arduino to the exposed pins/connector and just make this work. but I don't know what the pins do/what I should be looking for.
I've worked out the manufacturer labeled the board connector incorrectly, poking around with a multimeter allowed me to work out what was actually Strobe/Data/Clock properly.
Below you can I've picked some random digital pins and assigned them, if I plug the display in I get random characters on the screen for a second before it turns off. I just don't fully understand how I would simply send a word like 'Hello' to it. Can anyone help give me an example?
// 3 output pins to a 4094 8-bit shift register
int PIN_LCD_STROBE = 5; // Out: LCD IC4094 shift-register strobe
int PIN_LCD_DATA = 6; // Out: LCD IC4094 shift-register data
int PIN_LCD_CLOCK = 7; // Out: LCD IC4094 shift-register clock
void setup() {
// put your setup code here, to run once:
pinMode(PIN_LCD_STROBE, OUTPUT);
pinMode(PIN_LCD_DATA, OUTPUT);
pinMode(PIN_LCD_CLOCK, OUTPUT);
}
void loop() {
// put your main code here, to run repeatedly:
}```
I found a couple of good guides a) on how a shift register works and b) on how you have multiple:
Sadly there seems to be a slim amount of information on the actual shift registers I have and then obviously how that would work with a display output instead of LEDs
I'm really not too sure where to start on this one at all
Now that you have worked out the shift register this make more sense. They use the two shift registers to set up the input to the DLG3416 and then use the strobe to set the data/command information. Figure out how the shift register pins are connected to the display pins. Then you should be able to use the display data sheet to figure out the data stream needed.
How is this project coming along? Did you figure it out or do you need more help? If you have the connections between the shift registers and the display I can help with some code.
