UART/SERIAL VGA Controller

[pyromaniac4382]

I am currently working on a z80 computer. I have no output so far to a screen. I could hook up a UART & RS-232 level shifter then off to a PC running a terminal emulation, but I want a stand-alone system at the end of the day. I picked up a VGA monitor and a PS/2 keyboard on the cheap and would like to use that. So the question is, how would you output to a VGA monitor? I really only want a serial terminal, but later could dabble in generating actual images. I figured what I could do is take the output of the UART, and somehow show this text on the VGA monitor. Where do I even start?

[PepeK]

Z80 and VGA output ?  You need something like videocard for your Z80. Would not it be better to use some modern computer having HDMI output, sound, keyboard  and a lot of Linux based software like Raspberry ? Or is your plan to reinvent a wheel ?

[mariush]

I'd recommend using another microcontroller to act like a video card, taking uart/i2c data in and output s-video or composite signal, generating something like 320x240 or 640x480 in real time or something like that.

With a bit of effort you can output vga to a monitor as well... otherwise, there are svideo/composite to vga converters out there.

 

[Kjelt]

Did that with some old SAA Philips teletext chip a long long time ago.
Then there were also serial input video text overlay cards costing a bundle.
Nowadays I would just buy an old laptop with RS232 and be done wit it

[geek]

Just make your own video card using CPLD/FPGA

[westfw]

If you're not intent on building it yourself, you could use one of these modules:
http://microvga.com/
there are a lot of projects that use an Atmel AVR or other microcontroller to drive a VGA monitor at relatively low resolution.  here's a couple: http://tinyvga.com/

If you're interested in building things yourself, a good place to start would be with Lancaster's classic "TVT Typerwriter Cookbook": http://www.tinaja.com/ebooks/tvtcb.pdf

[Melt-O-Tronic]

If you want the easy way out, look at the Picasso µVGA-III.  Connect via serial, program & go.  It has a micro-SD slot so you can put pre-generated graphics on board that can be called up via serial commands.  You can do animation or video that way.

https://www.sparkfun.com/products/11767

[rob77]

I would try to find a ISA VGA crad not a problem to drive a ISA card with a 8bit CPU or micro.