Basic pocket computer display modification

Hi ben. I was watching old versions of your show and was wondering what is involved in changing the code for your basic pocket computer to work on a 20 by 4 display instead of a 16 by 4. I have tried messing around with the code but with no luck. Thanks in advance.

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Former Member over 11 years ago in reply to Former Member +1

WARNING! I DO NOT HAVE ANY HARDWARE TO TEST THIS WITH! THIS MAY STILL BE BROKEN! tl;dr Now that that's out of the way, here's a (potentially) fixed copy of the script: https://gist.github.com/zanothis…

ryan27968 over 12 years ago

is there no one who can help me here?
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benheck over 12 years ago in reply to ryan27968

Did you use the original source code? That was meant for a 20x4 display.

-Ben
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ryan27968 over 12 years ago

original? what do you mean?
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benheck over 12 years ago in reply to ryan27968

These files.

Attachments:
1273.pocker_BASIC.zip
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ryan27968 over 12 years ago in reply to benheck

this is the same code that i originally used, but it still does not work. this is written for a 16 by 4 not a 20 by 4.
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rhyse302 over 12 years ago in reply to ryan27968

Did you use the 4 bit monitor?
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ryan27968 over 12 years ago

Yes. my setup is EXACTLY the same except its a 20X4 screen.
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rhyse302 over 12 years ago in reply to ryan27968

It should work. It could be you need to use a special format or there is a flaw in the wiring.
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benheck over 12 years ago in reply to ryan27968

Ah, you probably need to re-arrange screen memory so it doesn't overflow the lines.

Look through the code for instances of 16, or multiples thereof.
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Former Member over 12 years ago in reply to benheck

crossposted to a new thead

I am too having problems getting my 20*4 screen (https://www.sparkfun.com/products/9568) working. I tried changing anything I could imagine having anything to do with the number of columns in the lcdChar (), doFrame () and setup () routines. Do you know which lines exactly must be changed in order to get a clean output?

thanks.

___________

Edit (13.8.);

I got it PARTLY working! THE 4 RIGHTMOST CHARS IN THE FIRST LINE ARE STILL MISSING AND DISPLAYED AT THE BEGINNING OF THE THIRD LINE. Anyone got help? For anyone who wants to know how, I changed the following lines in Tinybasic_2.ino (you find it here: http://www.element14.com/community/thread/25177?start=14&tstart=9)

Line Nr.	From (original code)	To (modified code)
23	int screenMem[72];	int screenMem[76];
1481	if (cursorX < 16) {	if (cursorX < 20) {
1489	if (cursorX == 16 or c == 10) {	if (cursorX == 20 or c == 10) {
1491	for (int xg = 0 ; xg < 16 ; xg++) {	for (int xg = 0 ; xg < 20 ; xg++) {
1494	screenMem[40 + xg] = screenMem[20 + xg];	screenMem[40 + xg] = screenMem[16 + xg];
1495	screenMem[16 + xg] = screenMem[56 + xg];	screenMem[20 + xg] = screenMem[56 + xg];
1503	doFrame(56);	doFrame(60);
1535	lcd.begin(16, 4);	lcd.begin(20, 4);
1537	for (int xg = 0 ; xg < 72 ; xg++) {	for (int xg = 0 ; xg < 76 ; xg++) {
1543	doFrame(56);	doFrame(60);