Serial Graphic LCD keep crashing

hi,

I just got a Serial Graphic LCD 160x128 from here.

sku: LCD-08884

When I hook up this LCD with Propeller MCU for the drawing.

It will keep crash after some drawing command.

Even just send the text to specific location will crash after a while

repeat

LCD.move(50,50)

LCD.str(“Hello World”)

DoSomeLongDelay

The code above is enough crash the LCD after a while.

I tried use all different baud rate and the result still same.

Even before crash, sometimes the location of display will shift and become “Hello WorldHello World”

When I start to drawing box,line or circle, it will crash like hell.

It’s totally useless if I need display some data.

Any idea about this LCD back?

Thanks

Are you sure that your power is good - and stable - and that all power connections to the Lcd are good? To check your power - place a reasonably “full” screen on display - and leave it untouched for several hours. (we don’t yet know if power is the culprit)

Also - try adding more delays between successive writes to the Lcd - see if this helps. (I note you’ve done this - make even longer)

Last (desperate) idea. Wonder if some buffer is being over-flowed/corrupted? Is it possible for you to send a “Serial-Controller RESET” Command - at reasonable intervals? You would then have to re-write your screen - this may give you some clue as to what’s causing this behavior.

That the serial backpack does not process CR ($0D carriage return) or LF ($0A line feed) at all. It appears the code for them was for some unknown reason removed from an earlier version. If you’re planning on writing any amount of text to the screen you’ll have to do additional programming to cover these oversights. If you see garbage characters, it may be that you’re using CR/LFs in code and that’s how the backpack draws 'em.

I’ve had an open issue on this problem since August, but haven’t succeeded in garnering the attention of the up-to-their-eyeballs-in-alligators tech staff.

One question on your problem, what voltage are you using to power your Big Bertha LCD?

_richard

I’ve been experiencing trouble on this LCD since I got 3 of them for a project I have. This display when drawing boxes and printing ASCII characters in the same screen at different coordinates prints garbage sometimes and erases areas of the screen or draws lines incorrectly at other times. All these occur randomly. Power voltage is above 6.4 V, serial communication routines include delays that prevent comm errors. We are certain all characters sent form the MSP430 being used get to the display, but we suspect the backpack has a lot of bugs in the firmware.

Any comments or thoughts on this? In the case of a buggy backpack, has anyone fixed them yet? What development tool woul be required to reprogram the backpack with a new firmware?

Thanks for your help and best regards from Mexico City

Pablo

I have re-writen the firmware for the small display 128*64. I don’t have the big display so my code at present has support for that removed as I have no way to test my changed.

The mirco controller is an Avr and there is a standard ISP header on the board so if you program avr’s the update is straight forward.

I posted in the new product section a couple of days ago offering to let SparkFun have my code back provided I could test with a big display.

If you want my updated code for the small display let me know.

ifor at blueyonder.co.uk

Hi,

I would really be interested in testing your code and adapt it to the huge LCD. I have a question…the ISP connector on the backpack is not soldered right? I noticed 6 pads I assume are used for the ISP interface.

Thanks for your response.

Pablo

Yes I soldered a header onto the 6 pins. I will have to take them off if I use it in my project finaly but putting a bootloader on should be possible.

email me and I will let you have my code as is. ifor at blueyonder.co.uk

Ifor