*.*sure*,*
eh what characters
easier to read eh!
but wasnt teh sam emulating only48 or 16k spectrum supposed to be 20%
faster?
so you mean they havent used the dma at the 17kb per frame block copy search
speed to do anything much really other than copy the data the z80 has
already created to the screen wouldnt the z80 be better copying it there in
the first place?
while the dma is doing this does that mean the bus is tied up?
wouldnt it be better to work out how often the z80 needs the buss for the
next few instructions and use smaller blocks so that teh bus wasnt tied up
for too long? the dma cant rotate such created polygons - couldnt be used
for matrix manipulation ideal for block copy and search also for inputs and
outputs
dont get one thing though
zilog reckons teh 4mhz z80 copies 200kb a second - plenty for hi extended
density discs with the wd1772chip which should be able to handle nearly 50mb
and if that was part of a serial directory trasck record who knows how much
data
velesoft reckon the dma for the 128 is around 17kb per frame
which kind of ties in with the speed of video ram contention
but what i dont get is fidzi speed test have you seen it it reckons sam can
have 1.2mips
this doesnt tie in with anything at this speed the processor alone could
shift over 450kb a second eh?!


2009/8/6 LCD <[email protected]>

> In ZX Spectrum DMA modification of Elite the DMA is used only to copy the
> buffer to screen area, not for the vector calculations. I never saw SAM
> Elite, but I think, it is using Mode 1, right? In this mode SAM is much
> slower. The game would work much better in Mode 2 or Mode 4 (with
> alternating screens and deleting only used pixels).
> Roger, please use "*.*" and "*,*" characters in messages. This will make
> them easier to read.
>
> Roger Jowett schrieb:
>
>> http://www.zxspectrum.it/
>>  mb-02+ rom here for real spectrum emulator only was doom on the disc?
>> the version of elite i cant work out if it is faster than the sam version
>> or not cant see much benefit for a dma with vectors - spell checker mebbe
>>
>> 2009/8/6 Roger Jowett <[email protected] <mailto:
>> [email protected]>>
>>
>>    tasonc has three programs
>>    1 basic loader to be saved to the +d disc
>>    2. basic you might need to add a pause statement in here if using
>>    an emulator
>>    3 the code
>>    the screen should whipe down from the top and you need to be in 48
>>    basic on the 128 for some bizzarre reason?
>>
>>    2009/8/6 Roger Jowett <[email protected]
>>    <mailto:[email protected]>>
>>
>>        http://www.worldofspectrum.org/infoseekid.cgi?id=0000210
>>                unfortunately have to use this one so no idea if they are
>>        viruses or whatever
>>                had to use this one as the library here in laimavady spends
>>        their time blocking every data transfer i attempt to make
>>        naaast better to do
>>                http://www.chmpdf.com/archives/sinclair/unsorted/apps/a/
>>
>>
>>                2009/8/6 Thomas Harte <[email protected]
>>        <mailto:[email protected]>>
>>
>>            Didn't the entirety of Take That, with Robbie, once play
>>            Bomberman on
>>            a single Amiga on Gamesmaster? That must have been at
>>            least three on
>>            the keyboard, assuming I didn't make it up.
>>
>>            Ant Attack would actually work really well on the Sam.
>>            I've never seen
>>            the original code, but by my reckoning it's a forward
>>            raycast into a
>>            triangle grid - Ant Attack having only one size and look
>>            of block. So
>>            it'd be really cheap to compute the minimal set of pixels
>>            that must be
>>            replotted to perform a scroll while leaving the same
>>            coloured blocks
>>            alone.
>>
>>            Don't think it's a 16kb game though - I stole the map for
>>            a PC game
>>            once & I think that may have been 16kb on its own.
>>
>>            On Tuesday, August 4, 2009, the_wub ! <[email protected]
>>            <mailto:[email protected]>> wrote:
>>            > wow thanks for the link, his site is a hoot :D
>>            >
>>            > and I was definately wrong about it being 16k :)
>>            >
>>
>>
>>
>>
>>
>

Reply via email to