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Can't set PMW frequency so LED fans are flickering/strobing

Posted: Wed May 19, 2004 4:00 am
by NeilFawcett
I'm having problems setting the PMW fequency on my MX4. The default frequency makes my LED fans flicker quite badly.

If I run BootEdit from the CD, I can set the frequency (interactively) to a higher rate and the flicker goes. However, I cannot seem to write this setting to the unit such that at a reboot this is the standard value.

I tried also setting the default boot screen using this program and it wouldn't work. In the end I had to use the option in LCDC to set a screen as a default (welcome) screen.

Is there something odd about BootEdit that would mean the values are not sent to the unit for its default boot up values?

note: I've tried running BootEdit with LCDC running and without it runing. The fact I can interactively change values on the MX4 shows its communicating with it. It just wont set the values as default boot up values though :-?

Posted: Wed May 19, 2004 10:15 am
by Miles
Hello...

Have you checked this link out...?

http://www.lcdforums.com/forums/viewtop ... +frequency

PWM base frequency and startup PWM base frequency are two different functions...

Posted: Wed May 19, 2004 3:25 pm
by NeilFawcett
Miles wrote:Hello...

Have you checked this link out...?

http://www.lcdforums.com/forums/viewtop ... +frequency

PWM base frequency and startup PWM base frequency are two different functions...
Exactly what I'm trying... I'm using BootEdit to set the defaut frequency at start (bootup). It changes it there and then when I set the new frequency, but when the machine is restarted the new setting has been lost.

Infact, even if I change the welcome screen in bootedit this isn't remembered either. There's a fundamental flaw here...

Posted: Wed May 19, 2004 4:04 pm
by Miles
And you can still communicate with the unit?? Turn the backlight off/on, contrast up/down?? :-?

Posted: Thu May 20, 2004 2:17 am
by NeilFawcett
Miles wrote:And you can still communicate with the unit?? Turn the backlight off/on, contrast up/down?? :-?
Yes... I run BootEdit (from the power_on directory on the cd) and set the Com and speed and "connect"...

As I change the display I can see it changing on the Unit.

If I change the GPO frequency I can see the LEDs on the fans changing. ie: At a higher frequency I get rid of my annoying strobing.

I then click the write to unit option.

HOWEVER, on booting up, the welcome screen is the old/previous one I set in LCDC, and the GPO frequency is back to the lower rate.

The backlight or contrast also go up and down, but again are lost at reboot.


On the little window that opens up for the GPOs the frequency drop down is always blank. If I set it to a high value, close that window (by clicking the main window behind) I can see the value affects the unit, but if I go back into the GPO window again, the drop down is blank again.

I've tried running BootEdit with and without LCDC running.




Maybe you can tell me how you would expect to set the default boot up GPO frequency?

I do hope this isn't a problem with my brand new MX4!


NOTE: Each time I press "write to unit" the display gets more and more corrupted. User definable character 1 pops up each time one more space across the top line. So if I press "write to unit" 10 times I get the character repeated 10 times across the top times by the end of it.

It's almost as if BootEdit isn't communicating correctly with the MX4.

Posted: Thu May 20, 2004 1:52 pm
by Miles
Please see your email... :)

Posted: Thu May 20, 2004 3:19 pm
by NeilFawcett
Miles wrote:Please see your email... :)
I have (now) emailed you... You have sent me a .MEM file and I am now waiting for the uploader program...

Not quite sure how this is going to help, but I'll gladly give it a go...

Posted: Thu May 20, 2004 3:26 pm
by Miles
I sent it to you in the first email...sent it again...I just want you to reload the mem file to unit default settings and we'll go from there!! :D

Posted: Fri May 21, 2004 1:45 am
by NeilFawcett
Miles wrote:I sent it to you in the first email...sent it again...I just want you to reload the mem file to unit default settings and we'll go from there!! :D
After uploading the MEM file twice I then rebooted.

The welcome message had been resset to the default one.

When in windows I closed LCDC and run BootEdit. It mis-behaves in the same way.

ie: On a reboot it has not set the welcome message, contrast, brightness or the PWM frequency.

Posted: Fri May 21, 2004 2:08 am
by Mat-Moo
AS LCDC is working, have you tried to set the boot screen from LCDC? Just create a screen as normal (untick it so it does not display) then use the "Save as power on" button at the bottom right of the screen builder...

Posted: Fri May 21, 2004 5:56 am
by NeilFawcett
mat-d-rat wrote:AS LCDC is working, have you tried to set the boot screen from LCDC? Just create a screen as normal (untick it so it does not display) then use the "Save as power on" button at the bottom right of the screen builder...
I mentioned this in my original post:-
I tried also setting the default boot screen using this program and it wouldn't work. In the end I had to use the option in LCDC to set a screen as a default (welcome) screen.

BootEdit cannot appear to set the welcome screen or indeed ANY settings. They are all lost when the system is shutdown & restarted.

If LCDC could set the default PWN frequency at startup I have little doubt it would work. Unfortunately only BootEdit appears to have this option, and it cannot appear to do it :(

As it stands my unit is useless for the main purpose I bought it for. It cannot control my (LED) fans as it makes them strobe/flicker too badly with the default startup frequency setting.

Posted: Fri May 21, 2004 2:29 pm
by Miles
I can't seem to get it working either....hmmm...interesting...I'll see what I can figure out!! :D

Posted: Sun May 23, 2004 7:28 am
by Mat-Moo
Well you can do it in LCDC but not as a set function. Up can send commands direct to your screen though, go into the "Configure/Test" section then select "Test Display", you can now (via the "Text" section) send anything to your screen. The command to "Remember" the PWM base frequency (from the docs on their website) is [254] [197] [index] where index is 0 to 15 (see manual). So to send that to the screen in the "Text" section type [##254,197,index] where index is of course 0..15. If you just want to test the frequencies, use [254] [196] [index] (in LCDC [##254,196,index] and of course make sure that a gpo is on (command [254][87][index]) and to change the % use [254][192][index][value].

Posted: Mon May 24, 2004 3:03 am
by NeilFawcett
mat-d-rat wrote:Well you can do it in LCDC but not as a set function. Up can send commands direct to your screen though, go into the "Configure/Test" section then select "Test Display", you can now (via the "Text" section) send anything to your screen. The command to "Remember" the PWM base frequency (from the docs on their website) is [254] [197] [index] where index is 0 to 15 (see manual). So to send that to the screen in the "Text" section type [##254,197,index] where index is of course 0..15. If you just want to test the frequencies, use [254] [196] [index] (in LCDC [##254,196,index] and of course make sure that a gpo is on (command [254][87][index]) and to change the % use [254][192][index][value].
So, if I do a line with this (exact) text:-
[##254,197,8]

That will set the GPOs frequency to whatever 8 is (eg: 560hz or the like). After a reboot it should remember it?

Posted: Mon May 24, 2004 4:47 am
by Mat-Moo
Yes, it should.