Home

Data-Gear DMA

Submitted by Dan Dooré on Wed, 2007-04-25 12:22. Hardware


Velesoft


Velesoft


2005-

8-bit DMA interface for Z80 based machines including the Sam Coupé.

Full details at http://velesoft.speccy.cz/data-gear.htm

Quote:

“DATA-GEAR is DMA interface for 8-bit computers with Z80CPU. DATA-GEAR is connected to socket for Z80CPU, there’s no need any hardware modifications in your computer. DMA chip use direct access to memory or port. Transfer of linear data block (max. 64kB) memory to memory / memory to port / port to memory / port to port. For computers with max. CPU speed 4MHz is used Z80DMA chip, but for faster computers (SAM COUPE=6MHz, ZS SCORPION TURBO=7MHz …) is need use DMA chip at 6-8MHz. DMA chip is programmed via port 11(#0B) = MB02 compatible. On board is extra switch for change programming port to 107(#6B).

Max. speed of data transfer on ZX128+ is 17.3 kB(17727 bytes) / frame = 865.6 kB(886350 bytes) / second”

» login or register to post comments

For those of us who don't read Czech,

Submitted by ascii on Wed, 2007-05-09 20:27.

For those of us who don’t read Czech, what can you actually do with this chip? Does it contend with the Z80B for memory bandwidth while it runs?

» login or register to post comments

Have a look at:

Submitted by Dan Dooré on Tue, 2007-05-15 19:07.

http://www.worldofspectrum.org/forums/showthread.php?t=15109

Also as mentioned on raww.org:

“Data Gear DMA Interface
Posted By: icabod, Friday, March 16, 2007 - 01:29 PM

One of the great things about the MB02+ disc system is/was the DMA. Using the device’s built-in Zilog DMA chip you could throw data around at very high rates, meaning some nice FX (such as Multitech and other lovely graphics effects) were possible. Over on the WOS forum Velesoft, the Czech hardware guru has mentioned the Data-Gear, an internal mod that provides the same DMA functionality as the MB02+, without needing an actual MB02+. Nice, huh? In fact, here’s an example of what you can achieve - the green area is the time spent doing DMA. Yep, entire screen scrolling in about half a frame.”

» login or register to post comments

prague for the second time and no reply to emails

Submitted by rogerjowett on Tue, 2009-04-21 10:53.

wonder if it is compatible with the atom ide interface?
finally have received a google earth image of a rough street area
luckily no address or phone number
we might be bale to communicate
wonder how many colours the dma could make appear on a scan line just by changing a palette entry - wonder why they use the 128 spectrum clock speed when even mode1 on sam is slightly faster than this
there is software for the dma at mb-02+ website
but i arent too sure if it would work on sam though tere is a 48 version of elite so that mite?!

actual manufacturer

http://www.truppel-online.de/Fotos/Seite.html

http://www.8bc.com/sinclair/

includes some multitech screens as does velesoft site though none are interlaced i dont think

http://velesoft.speccy.cz/data-gear.htm

http://www.youtube.com/watch?v=k-tPMy9Q-zM

i ahve a video on my u toob but not sure what it does or how to use it not quite as friendly as +D
certainly no tasword +2 converted for it like sam

http://www.youtube.com/watch?v=k2L1cYzizKM&feature=related

is it any faster than sam version? woudl need to run in real spectrum emulator as thats the only one with dma support at the moment any one got sam elite or shall i just use oringal 48 version in simcoop?

» login or register to post comments

English Update

Submitted by Dan Dooré on Tue, 2007-09-18 07:32.

Velosoft has updated the page in English, quote from site added above.

» login or register to post comments

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.