HD44780 LCD support compiled in?

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DG0OFZ
Posts: 26
Joined: Thu Jun 07, 2018 6:53 pm

HD44780 LCD support compiled in?

Post by DG0OFZ »

Hi,

I've connected a HD4478 LCD module to my Raspberry Pi 2 which is running Pi-Star.
The wiring is done like described in https://github.com/g4klx/MMDVMHost/blob ... ME.HD44780.
I'm not using I2c.

But it isn't working. posting.php?mode=post&f=3#
The Display shows nothing.

I've read that HD44780 support has to be compiled in to the mmdvmhost program.
Is the mmdvmhost version, contained in Pi-Star, compiled with HD44780 support?

If so, what do i have to configure to get the display working?
The usual things are already done: Set the "MMDVM Display Type" to "HD44780", in Expert Mode the MMDVMHost settings for "HD44780" are at their defaults. My Display is a 16*2 type.

Some lines from my /etc/mmdvmhost:

Code: Select all

[General]
Display=HD44780
...
[HD44780]
Rows=2
Columns=16
Pins=11,10,0,1,2,3
#I2CAddress=0x20
PWM=0
PWMPin=21
PWMBright=100
PWMDim=16
DisplayClock=1
UTC=0
Any hints?

73s de Thomas, DG0OFZ
73s de Thomas, DG0OFZ
DG0OFZ
Posts: 26
Joined: Thu Jun 07, 2018 6:53 pm

Re: HD44780 LCD support compiled in?

Post by DG0OFZ »

Good news:

The Display is now working. Forgot a GND wire to the displays R/W pin...

So there is one question left:

Is the mmdvmhost version, contained in Pi-Star, compiled with HD44780 support?

73s de Thomas, DG0OFZ
73s de Thomas, DG0OFZ
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w7efs
Posts: 335
Joined: Sun Apr 22, 2018 4:26 pm

Re: HD44780 LCD support compiled in?

Post by w7efs »

Examine the "MMDVM Display Type:" pull-down menu in the "MMDVMHost Configuration" section of the Configuration page. If your display type is listed there then your answer is "yes".
DG0OFZ
Posts: 26
Joined: Thu Jun 07, 2018 6:53 pm

Re: HD44780 LCD support compiled in?

Post by DG0OFZ »

Hi w7efs,
w7efs wrote: Sun Oct 21, 2018 5:39 pm Examine the "MMDVM Display Type:" pull-down menu in the "MMDVMHost Configuration" section of the Configuration page. If your display type is listed there then your answer is "yes".
Are you really sure?

I can't believe this, because there are three things:

- If I use the original mmdvmhost binary or my self-compiled one (with HD44780 support), I see the same options in this pull down menu.
- As far as I understand, one has to decide, which display to compile in because there is only ONE makefile for one display type. I think this way you can't compile multiple Displays into it.
- I've had a look at the php file, which is generating the HTML page for configuring the display type. One of the lines there for the display types is:

Code: Select all

<option <?php if ($configmmdvm['General']['Display'] == "HD44780") {echo 'selected="selected" ';}; ?>value="HD44780">HD44780</option>
I read this so, that only the "selected" value is generated dynamically. All the other statements are static.

73s de Thomas, DG0OFZ
73s de Thomas, DG0OFZ
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MW0MWZ
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Location: Wales, UK
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Re: HD44780 LCD support compiled in?

Post by MW0MWZ »

I don't use the off-the-shel Makefile(s) :)

So yes really - there are multiple display types compiled into the one binary.
Andy

73 de MW0MWZ
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VK3KYY
Posts: 58
Joined: Fri Aug 03, 2018 1:31 am

Re: HD44780 LCD support compiled in?

Post by VK3KYY »

Sorry to ask a stupid question, but is the HD44780 connected via I2C on the modem board, and what "Port" should I select ?? Modem ??

I've connected mine via that port but I'm not seeing anything :-(
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