I have a project built here and would like to know if it is possible and how I could add a LCD alpha numeric display or TFT Display. And It will need to display 20 different message.

I have uploaded a pdf with the project sch. can someone help me figure out if and then how I can install a display and program the display.If possible I would like to use the Sharp LQ043T1DG01 display or something like the Lumex LCM-S04004DSR.


Thanks for any help and advice.

 

Read the data sheets to learn how to program them. I am not familiar with any way other than using microcontrollers.

What do you want it to do in relation to that circuit?

 

Hi,

I am just wanting the display to read what band antenna is being used from the circuit .

If you look at sch. it has it lighting a led to display what antenna is being used.What I am looking for is the display to say:

Yaesu Antenna 160 meters when its on the Yaesu part of the circuit

Icom Antenna XXX meters when its on the Icom circuit

As u look at the diagram you will see some of the antenna selections are combined on the Icom and Yaesu side these are now all seperated and it actual is controlling 10 2n4001 for the relay ground .

Thanks for looking at it for me and helping.And thanks for the help on the LM339's that you gave me.

 

You're quite welcome to the help, it is good to know it's appreciated!

What is the background to this project? Is it a personal one? Is there a deadline?

How long are the messages? Could a smaller monochrome LCD display do the job, perhaps two rows of 16 characters?

I would recommend that you tackle the Sharp display only after playing with some simpler displays first, unless it is a project requirement.

 

There is no deadline this is just a project I started on my own there is no deadline or anything like that.
I just wanted to add the lcd display in it if it could be done without to much trouble.

I think the smaller 1 will work fine.The messages will be as followed:If it can be done

Message 1: Yaesu 160 M
2 Yaesu 80 M
3 Yaesu 40 M
4 Yaesu 30 M
5 Yaesu 20 M
6 Yaesu 17 M
7 Yaesu 15 M
8 Yaesu 12 M
9 Yaesu 10 M
And then the same for the Icom side of the circuit.Hope I am explaining it so as you understand what I am trying to do.

And again thanks for your time and patience with me .

 

I agree with engine1. This project is best tackled with a microcontroller. Writing messages to a 2-line LCD display does not lend itself to discrete logic.

hgmjr

 

I have not implemented such a display, though have looked into it briefly. I can point you in the right direction, and might be able to help with some specifics.

The HD44780 is a commonly used part by hobbyists and professional engineers alike.

These two articles might be a good read. Can't say I've read them though!

http://www.epemag.wimborne.co.uk/lcd1.pdf
http://www.epemag.wimborne.co.uk/lcd2.pdf

Have you ever delved into microcontrollers?

 

Well Ifigured it would have its on mcu was looking for help on picking one that would have the memory to hold all the messages I needed and help tying it into my project circuit to make it display the proper message at proper time.

I belive the HD44780 will do what I am wanting.

 

The device HD44780 is the LCD interface device that implements the command protocol for character-type displays. It alone has only a small amount of user memory used to hold user defined special characters.

It is not likely to do what you want to do without a microcontroller to configure it.


hgmjr

 

so basically you want to display what antenna is selected on the LCD either 1 of the 7 YAESU or 1 of the 7 ICOM bands..... These antenna selections are usually displayed on an LED array when selected and you want to tap off of those LED's so the microcontroller can determine what band or antenna it is using....

So you will need a microcontroller with atleast 6 pins to control an LCD (HD44780 LCD's can operate in 4 bit mode, so you would only need 4 datalines, 1 for R/S, and 1 for strobe) and atleast 14 pins for inputs from the LED's, unless you use a multiplexer for the inputs to reduce the input pin requirements.... There are several 1 of 8 mux's (DM74LS151 1 of 8 Multiplexer) available and you could use one for each band.

If you use a mux, possibly a Pic16F628A should do the trick for you.

 

Thanks for the information everyone.

After reading a ton and talking with my brother we only need the display to read 9 messages as it does not matter what radio is plugged into the interface they all are using the same output to relay transistor.Yes saying radio brand would have been nice but I cant find a mcu with enough inputs on it to do it that way so I am looking looking to just get 9 messages to display.

Bmorse is there a chance you could draw me a sketch using the mcu an the mux and showing me how to connect it to my project. Droping the number of messages I should not have to use 9 mux will I?

The original sch shows 7 antennas but I have broken them apart so there are 9 ant now .I hope I have explained it where everyone can follow what I'm saying.

Thanks agn everyone for the input and help.

 

I will see what I can put together for you....

 

Ok, you should be able to do what you want with this setup, basically 8 out of 9 ant inputs are multiplexed using the 74LS151, the 9th input is on its own pin on the microcontroller. The LCD connections are for any HD44780 compatible display that is wired in 4 bit mode....... This is just a quick schematic I threw together in a few minutes, so if anyone has any improvements hope they speak up, but otherwise I think this should get you going in the right direction....

You could also check out Roman Black's 1 wire LCD control protocol..... if you want to free up some more pins on the microcontroller.....

This project is not that elaborate in the programming sense (won't use up much of the memory available in the uc), so it should leave you plenty of room for more than 9 messages (set up the messages in a lookup table).....

Basically with the circuit, the pic will select which input to check by setting the appropriate address with the 3 address pins (A,B,C), and the resulting data will be reflected with the 2 output pins (W, Y) of the 74LS151 mux.
I attached the 74LS151's truth table so you can see what the results should be.....





My .02

 

Bmorse,

Thank you ever so much for your time in this and drawing this out for me.I hope that I can get this done in next couple of weeks and post how it comes out.

Again Thank you all for your help.

Tim

 

BMorse,

Thanks again for your help.I just got 1 question for you.

On the sch you drew up for me what are r2-4 for and what value should they be? 100-220K?



Sorry for having to ask so many dumb questions but this is all new stuff to me.
Thanks for your help and patience with me.

 

I'm not sure R2-4 are necessary, but correct me if I'm wrong. Output low of the 74LS151 is supposed to be a maximum of 0.4V and the PIC should take anything below 0.8V to be low.
The 74LS has an 800uA high output so any resistor to ground would have to be pretty high value - I'm guessing 5K would be safe.

 

BMorse,

Thanks again for your help.I just got 1 question for you.

On the sch you drew up for me what are r2-4 for and what value should they be? 100-220K?



Sorry for having to ask so many dumb questions but this is all new stuff to me.
Thanks for your help and patience with me.

they should be 10K to 47K.

 

I'm not sure R2-4 are necessary, but correct me if I'm wrong.

They are not really necessary, but I always use either pullups or pulldowns for address lines....