bret@orac.UUCP (Bret Indrelee) (05/19/91)
In article <845@taniwha.UUCP> paul@taniwha.UUCP (Paul Campbell) writes: [Question about 25MHz NuBus reply] > >No, this impression is something that Next marketting have done really well >in putting over - it's a 12.5MHz NuBus with a double clocked burst mode, >this means that for most accesses you put over it (68030s only burst >instructions and the RAM is on the motherboard, '040s require special >coding to make them burst - or alternatively you need special hardware >to support it) its only 1.25 x the speed of a normal 10MHz NuBus (in >fact the best thing you can do for the most common NuBus peripheral >(a framestore) is to reduce the single cycle latency to 2-3 clocks >a 2 clock 10MHz NuBus (200nS cycle) is much faster than a 4 clock >12.5MHz NuBus (320nS cycle)). > I don't know if it was good, marketting broadcasting that they had the NuBus running at 25MHz. I know of at least one hardware project where the engineer didn't even look at making his NuBus board work on the Next when it was found out that the bus clock ran at (we thought) 25MHz. Don't bother telling me that we should have double checked. NeXT time, maybe computer manufacturers should either follow the published standard or not bother calling it the same bus. -Bret -- ------------------------------------------------------------------------------ Bret Indrelee | <This space left intentionally blink> bret@orac.edgar.mn.org | ;^)