Re: Larkin, Power BASIC cannot be THAT good:
- From: Jan Panteltje <pNaonStpealmtje@xxxxxxxxx>
- Date: Wed, 10 Jun 2009 22:21:48 GMT
On a sunny day (Wed, 10 Jun 2009 16:45:32 -0500) it happened "Tim Williams"
<tmoranwms@xxxxxxxxxxx> wrote in <_RVXl.43024$Mf7.6069@xxxxxxxxxxxx>:
"Jan Panteltje" <pNaonStpealmtje@xxxxxxxxx> wrote in message
news:h0p14i$k4d$1@xxxxxxxxxxxxxxxxxx
It can be fun programming in asm to get max speed, I have done video on a
PIC
in asm for example, but if you have enough processing power why bother?
Video? In ASM? Hah, just the other day I tried getting my breadboarded Z80
to produce NTSC composite. Just bit banging out of a spare data bit or two.
No good, one instruction takes about an inch of scan, no time even to read
the next line, and the horizontal sync is terribly unreliable due to the
variable interrupt latency. With lots of prodding I made a few stable
pictures, nothing interactive. Definitely needs support hardware. An AVR
at 16MHz would probably do nicely though.
Tim
Hi, Tim, well, the 'video' PIC runs on the internal oscillator of about 4 MHz...
What it does is remove those annoying pulses that some DVD players insert,
the Dutch word is 'beeldverbeteraar', in English 'picture improver'.
This is the complete project files, including asm:
ftp://panteltje.com/pub/mvp-0.2.zip
This is what the thing look like:
ftp://panteltje.com/mpv-0.2-pcb.jpg
What it does is:
It first finds the V sync pulse, then samples the video black level for an empty line,
using a HC4053, then waits until just before where those nasty pulses occur,
and then replaces that area with the sampled black level.
Simple.
You may think it is illegal to remove those M * cr * v *s * on pulses, as normally
those are only inserted to prevent copying, but my DVD player, a Mustek,
*always* added those pulses, also on my own DVDs that I created myself, so I had to
design this to be able to make VHS tapes of my own DVDs.
Maybe helpful to somebody who has the same crap DVD player (I have put that one with
the garbage some time ago).
There was more wrong with that player.
.
- References:
- Re: Larkin, Power BASIC cannot be THAT good:
- From: mrdarrett
- Re: Larkin, Power BASIC cannot be THAT good:
- From: Jan Panteltje
- Re: Larkin, Power BASIC cannot be THAT good:
- From: mrdarrett
- Re: Larkin, Power BASIC cannot be THAT good:
- From: Jan Panteltje
- Re: Larkin, Power BASIC cannot be THAT good:
- From: Anssi Saari
- Re: Larkin, Power BASIC cannot be THAT good:
- From: Jan Panteltje
- Re: Larkin, Power BASIC cannot be THAT good:
- From: Tim Williams
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