AGM1264F Parallel Graphic 128x64 LCD with KS0107B Controller to Prop Sample Pro

kf4ixm

Hi all, i have an AZ Displays AGM1264F 128x64 Parallel Graphic LCD module, from BG Micro.·it has the KS0107B controller chip with 2 KS0108B driver chips.
http://www.bgmicro.com/index.asp?PageAction=VIEWPROD&ProdID=10816

Has anyone used one of these with the prop? I'm looking for pointers on how to connect this to a prop, (pretty sure i have this figured out) and how to send commands to it from the prop, (definatly don't know how to do this). If someone has used this display and could provide some code or an object to display text or graphics on this, i would greatly appreciate it. Even better, an object i could pass paramaters to, to display graphics or text. Something in .spin is highly preferred. Here is the datasheet for the display...

http://docs.bgmicro.com/pdf/lcd1030.pdf

Any help is greatly appreciated!

EDIT;
Ok, i did find the KS0108 128x64 parallel lcd driver W character disp in the obex, from reading the documentation in the ks0108v1.3.spin, is the 470 ohm resistors necessary? can i substitute a different value thats close if i dont have enough 470 ohms? Also has anyone used this object with good results, not to say it doesn't work, but just seeing if someone has had to do any tweaking to it in order to make it work for whatever reason.


Post Edited (kf4ixm) : 3/23/2010 2:10:48 PM GMT

kf4ixm

Also, from page 6 of the documentation above, it shows a schematic for the power supply, apparently it takes two separate supplies for the module, it says +5v and -10v for the lcd driving. what does the -10v mean? it would seem to me that from the schematic that the -10v should be +10v. from what i know the -10v would be the negative side of the 10v supply, the +10 would be the positive side of the supply.


From what i see the negatives from each ps are tied together and the varible resistor is tied between +5v and the -10v with the wiper going to Vo. the -10v thing is what has me confused. Shouldn't the -10v be +10v instead?

Post Edited (kf4ixm) : 3/23/2010 5:05:39 PM GMT

Leon

The -10V is needed for the contrast adjustment. I've got some character LCDs that work OK if that input is simply connected to ground, it's worth trying it. You could generate a negative voltage by toggling an output pin connected connected to a diode pump circuit, or you can get a chip that will do it.

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Leon Heller
Amateur radio callsign: G1HSM

kf4ixm

Ok, thanks Leon, i'll try that. i did find a circuit for a negative power supply that i may try later if needed...




Thanks for the reply!
I also found a voltage converter from maxim, a max1044 chip, good up to 20ma. i may go that route as it's all in one chip. got a sample on order.

Post Edited (kf4ixm) : 3/23/2010 5:37:44 PM GMT

Erik Friesen

I did a bunch of experimentation, and for some odd reason, anything smaller than 470 caused my screen to reset. It may have been a fluke. Anyway, its good practice for protecting your io.

kf4ixm

ok, Erik. Thanks for the reply, i will get some more 470's then and go from there. And thanks for the excellent documentation in the object, has really helped out alot. Also, did your display work good wit the Vee tied to ground as in the documentation? What did your module call for on the Vee?

Post Edited (kf4ixm) : 3/23/2010 7:17:19 PM GMT

kf4ixm

Ok, an update.
I have the display wired to a propeller proto usb board EXACTLY as per the documentation in the Demo_Lcd_Ks0108V1.3 (and believe me, i've double-checked 4 times), turns out that i didn't have to use a negative power supply for the display. Now when i load the demo onto the prop proto board, i get a solid black screen for about 3-5 seconds (sometimes less than that)·then the left side goes dim with the right side still black. i get no text, graphics or anything else, and it stays like that until i press reset or reload the program. Any ideas?

Also, about the VSS strip on the right side of the proto board, between the prop chip and where i have my ribbon cable attatched, is that vss on the 3.3v ps or for the 5v ps? I have the vss/gnd for the display connected here. I'm wondering if this is on the 3.3v side, would this be giving me the problems.

Post Edited (kf4ixm) : 4/14/2010 5:20:00 AM GMT

Erik Friesen

Make sure you don't have any solder bridges. You can try adjusting the delay within the driver from 90 to 180 or so. I don't have it in front of me, but it is about at the bottom of the driver. Some cheaper ks0108 knockoffs can't handle that rate the data is shoved at them, so you have to slow it down.

It wouldn't hurt to go over the configuration and make sure it is like what is the in docs. IE e to e r/w to r/w etc

I don't have a proto board, so I can't answer that one. Multitester?

PJAllen

Do you have the LCD connector figured right?

It looks like you have the LCD's pin_1, its GND/V_ss, connected to a fat orange wire and that's going to the Prop_Bd's +5V.· Or do I have it wrong?

Post Edit -- It's hard to tell from the 'img245' pick, but it looks like you're snaking it under that pot?

Post Edited (PJ Allen) : 4/14/2010 11:58:28 PM GMT

PJAllen

???

Seems to have dropped carrier.· Oh well.

+++ ATH

kf4ixm

it's hard to see it from the pic, but the orange wire is going to one side of the pot for contrast control. the other shorter orange wire you see on the other side of the pot connects to the vss pin 1 of the lcd to the vss strip of holes on the proto board (the vss strip of holes are directly under the pot). (it looks like it does go all the way through, but it doesn't)·i have another wire under the board that you can't see that runs from the 5vdc to pin 2 of the lcd.

PJ Allen said...

Do you have the LCD connector figured right?

It looks like you have the LCD's pin_1, its GND/V_ss, connected to a fat orange wire and that's going to the Prop_Bd's +5V.· Or do I have it wrong?


Post Edit -- It's hard to tell from the 'img245' pick, but it looks like you're snaking it under that pot?

kf4ixm

i think i may have some flux residue issues on the ribbon cable soldering, i'm gonna get some cleaner and clean that up and resolder this weekend. i kinda run out of time this week to work on it much and i may have got in a hurry when soldering.

@Erik
I did try the timing adjustment and it did have some effect, but it just changed on what side of the screen the block appeared, 45 i think was the one i used to cause that. i did change the pin configs on the d/i and r/w and i got some of the graphics and text,( there were some alignment issues with the text and graphics), but the display had two black lines going through most of it. which led me to think, ok i have some wires crossed up on the ribbon. well i checked the wiring 2 more times and i don't and also no solder bridges between pins. so this weekend im gonna clean everything up and resolder, this time, easy on the flux, lol.