Writing variables to parallel LCD.

Palli Steina

Hi all, first post to this forum.

Im using BS2 on Professional Development board from Parallax. I got a 2x16 parallel LCD screen from Parallax. I have run one of the demos that came with Stamp Works, and it displays just fine, so the connections and the display is working.

Now... the problem.

Im making a simple remote control for laser modulation. By pressing buttons A and B I change the frequency of the modulation by 1 hz at a time. That part of the program works great. But what I cant do, is write the status of the HZ counter to the LCD.

In every example I have found, the use of EEPROM and predefined messages is required, but I dont want that, I just want to write 1 Hz, 2 Hz, 3 Hz etc. whenever the button is pressed.

Current pins:
0 = Laser(Led)
1 = PB1
2 = PB2

5 = E
6 = RW
7 = RS
8 = DB0/DB4
9 = DB1/DB5
10 = DB2/DB6
11 = DB3/DB7

I would appriciate if you could point me in the right direction, either by a very shrot minimal initial startup code for the LCD and how to write a variable to it or just explain to me how it works! [noparse]:)[/noparse]

Either way, I will appriciate the help.

Thanks in advance,
Regards,
Palli Steina

Moskog

Something like this....?


' {$STAMP BS2}
' {$PBASIC 2.5}


LCD PIN 1 ' serial output to LCD on BS2 Pin 1
LcdBaud CON 32 ' Baudrate 19.2KHz with BS2
LcdLine1 CON $94 ' move to line 1, column on LCD
Hertz VAR Word ' Declare variable Hertz as a Word


...program code.....


SEROUT LCD, LcdBaud,[noparse][[/noparse]LcdLine1, "Frequency: ",Hertz," Hz] 'Write to LCD line 2 from top

...rest of programcode....

Palli Steina

Thanks for the answear Moskog.

But this is a parrallel LCD display, does that peice of code work for it?

Regards,
Palli Steina

Moskog

Oh, sorry, I did't see that. That code was for the serial LCD with backpack from Parallax.
I have no experience with the pure parallel LCD yet and I guess before I reach to figure out a good explanation someone else will give you good help.

Chris Savage

Hello,

To be honest I cannot believe we haven’t put something up. So what I have done is take the Stamp Works Experiment #11 code and remove the cursor animation and replace it with a simple counter loop that counts from 0 through 65535. This value is then displayed on line 2 of the Parallel LCD. There are two versions of the code and below is an explanation. I hope this helps and it will be listed on our Parallel LCD product page as well.

Parallel LCD Vars Leave.bs2 – This program demonstrates how to display up to a 16-bit numeric variable on a parallel LCD using the StampWorks Parallel LCD code as framework. To use this code, connect your Parallel LCD as per the StampWorks Kit Experiment #11 and then download and run this code. This version leaves leading zeros in values printed. This can often help preserve display formatting when items are printed to the right of the variable.

Parallel LCD Vars Strip.bs2 – This program demonstrates how to display up to a 16-bit numeric variable on a parallel LCD using the StampWorks Parallel LCD code as framework. To use this code, connect your Parallel LCD as per the StampWorks Kit Experiment #11 and then download and run this code. This version strips leading zeros in values printed.

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Chris Savage
Parallax Engineering

Palli Steina

Hi, Chris and thank you for your answear. This is what I call support!

This is exactly what I was hoping for and I really appriciate it. Was looking like I was going to have to take the dev board on site. [noparse]:)[/noparse]

Regards,
Palli Steina

Post Edited (Palli Steina) : 1/12/2009 8:06:25 PM GMT

Chris Savage

Palli,

Glad to help. The fact that this comes up so often really means we needed the example code anyway. I have been working with LCD displays since the Hitachi HD44780 chipset so I used Parallel displays long before the serial backpacks became popular. The problem is all my existing code is written in 65xx, 68xx or Z80 assembly. So today was good day to just write some example BASIC Stamp code. Take care.

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Chris Savage
Parallax Engineering

sylvie369

Excellent. Yes, this question does come up quite often, and it's important to have Parallax-supplied demo code.

Have you considered making this a "sticky"? It'll be a lot easier to refer others to it if it's up there at the top.

Chris Savage

Too many sticky threads can become a problem as well. Instead we’ll add the code to our website and we can always point there if need be.

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Chris Savage
Parallax Engineering