rcwlobe@cs.vu.nl (Reg Lobee) (03/21/90)
I am planning to built an additional 64k ram into my c64. I want to do this by putting another eight 4164's into it. Looking at adverbs I saw that the 4164 is available as 120 and 150 ns model. Because the c64 is a slow computer I think the cheaper 150ns type should be sufficient. Is this assumption correct? What is the exact relation between the speed of the processor and the rams? In other words: What is the slowest possible ram that could be built into the c64? I sure hope someone has a clear answer to this question. Reg Lobee rcwlobe@cs.vu.nl mcsun!botter!rcwlobe
scott@max.u.washington.edu (03/21/90)
In article <6056@star.cs.vu.nl>, rcwlobe@cs.vu.nl (Reg Lobee) writes: > I am planning to built an additional 64k ram into my c64. I want to do this by > putting another eight 4164's into it. Looking at adverbs I saw that the 4164 is > available as 120 and 150 ns model. Because the c64 is a slow computer I think > the cheaper 150ns type should be sufficient. Is this assumption correct? > What is the exact relation between the speed of the processor and the rams? In > other words: What is the slowest possible ram that could be built into the c64? > > I sure hope someone has a clear answer to this question. > > Reg Lobee > rcwlobe@cs.vu.nl > mcsun!botter!rcwlobe About the speed of chips, 150ns is more than adaquate for the C64. I can't be specific, but I can says these, an IBM XT/Compatible uses memory chips no faster than 150ns.
leblanc@eecg.toronto.edu (Marcel LeBlanc) (03/22/90)
In article <13476.2607039a@max.u.washington.edu> scott@max.u.washington.edu writes: >In article <6056@star.cs.vu.nl>, rcwlobe@cs.vu.nl (Reg Lobee) writes: >> I am planning to built an additional 64k ram into my c64. I want to do this by >> putting another eight 4164's into it. Looking at adverbs I saw that the 4164 is >> available as 120 and 150 ns model. Because the c64 is a slow computer I think >> the cheaper 150ns type should be sufficient. Is this assumption correct? >> What is the exact relation between the speed of the processor and the rams? In >> other words: What is the slowest possible ram that could be built into the c64? >> >> I sure hope someone has a clear answer to this question. >> >> Reg Lobee >> rcwlobe@cs.vu.nl > >About the speed of chips, 150ns is more than adaquate for the C64. >I can't be specific, but I can says these, an IBM XT/Compatible >uses memory chips no faster than 150ns. Yes, 150ns DRAMs are certainly fast enough. Using the PC/XT as a comparison is actually quite useful, since the C64 and the IBM PC run at about the same BUS speed. The C64 has a BUS cycle time of about 1000ns, and the IBM PC has a BUS cycle time of about 840ns (4/4.77 = 0.84 us [or 1.2 MHz]). If they are any less expensive (and they exist), you could probably use 250ns DRAMs in both of these computers. Marcel A. LeBlanc | University of Toronto -- Toronto, Canada "leblanc@eecg.toronto.edu" | and: LMS Technologies Ltd, Fredericton, NB, Canada ------------------------------------------------------------------------------- UUCP: uunet!utai!eecg!leblanc BITNET: leblanc@eecg.utoronto[.ca]