Video controller IC for a CRT controller

[yego]

the crt controller

Sorry for reviving a long dead topic, but I've read the topic not finding what I was initially looking for. I have got the 640x480 colour LCD pannel ( SHARP LM64C081 ) and initially wanted to controll it using the MC6845 controller with some glue from the XC9572XL CPLD. After a while I realized that one XC2C256 would do. Unfortunately I lack the pinout ( datasheet ) of the LCD pannel and its control waveforms.
I would appreciate any help you could provide.

BTW, Those who would like to use the old MC6845 CRT controller can download the datasheet below.

Thanks in advance, Yego

Warning
File deleted
Don't upload files that are freely available elesewhere on the internet, just post link instead:
**broken link removed**

 

[Bingo600]

crt microcontroller

@yego

Do you have some CRT-Controller code for the CPLD , that you would like to share (upload) ??

/Bingo

 

[yego]

crt controller z80 simple

@Bingo600,

I have been working on my controller design for a week now, so I'am expecting to produce some working code in about a week or so. Unfortunately it's gonna be for the 640x480 monochrome LCD pannel ( Hitachi LMG6222XUFE ), as I haven't got the datasheet for my colour LCD yet.
Nevertheless, I will post schematic diagram and some code as soon as I make it dance .

Rgds, yego

 

[ME]

application of 6845 crt controller

Try to read these links:

Video Generation with AVR microcontrollers:
http://instruct1.cit.cornell.edu/courses/ee476/video/index.html

Video DVM
**broken link removed**

Bingo On Your TV
**broken link removed**

AVR based TV cronograph
**broken link removed**

 

[yego]

lcd controller cpld xilinx hsync

@Bingo600

If you want to see my LCD controller design, you can follow this link **broken link removed**.
There is a general schematic jpg file, and complete VHDL code for this design.

Regards, yego

 

[Bingo600]

connect 6845 to a microcontroller

@yego

I cant find any schematic or VHDL code :-(
Did you post a link to it in that thread ??

 

[yego]

hd46505 crt data

@Bingo600,

Well, that's likely that you must be a member of the forum to see the files.
You should register there, to be able to get any files posted there.

Just in case you don't like registering in there, I'm sending you those files via your pm.

Regards, yego

 

[video_engr]

lcd controller cpld

I recently found a MC6845 in VHDL. Goes into CPLDs/FPGAs/ASICs.
Found it at www.digitalblocks.com

 

[maxer]

crt controller

You should DEFINITELY use fpga, consider using Spartan 3 starter as it costs less.
I already implemented a vga controller graphical 640x480 and text mode 80 x 25 in vhdl and i can ensure you that a microcontroller will not handle the neccessary timing for video generation on a screen 640 x 480.

regards

maXer

 

[yego]

practical applications of crt controller

I recently found a MC6845 in VHDL. Goes into CPLDs/FPGAs/ASICs.

6845 is a nice chip (design) but it's useless for FPGA environment.
The reason is quite simple. 6845 is a generic design suitable for a wide range of applications with different vertical and horizontal frequencies and resolutions.
PLD design, however, is usually aimed at some specific product with fixed resolution, V and H timings. CRT controller is basically a set of counters and multiplexers used to provide timings and video memory scanning. So IMHO the 6845 is an overkill with its multiple options, adjustable counters, and other bells and whistles. Moreover one needs to add a lot of extra glue circuitry to fit it in his design. So the 6845 core alone does not solve the problem. Usually a much simpler custom design would do saving a lot of FPGA resources for more needed options. Designing such a simple controller is really not much of a challenge even for a not very skilled designer. So why paying for something you're going to use just 10% of its functionality ?
There are of course some reasonable purposes to use 6845 core in certain design requiring flexibility and reconfigurability, but those are quite rare.
I wouldn't go for this core

Regards, yego

 

[video_engr]

hd46505 pdf

6845 is a nice chip (design) but ...

We have a tight time window to get out our product. As an enginner here I'm used for the value-added aspects of our product, not for display controllers. So far the Digital Blocks DB6845 looks pretty complete, and we have no complaints.