Whenever you see "EC" written on any 68020, 030, 040, or 060 it means that CPU has NO MMU and NO FPU
68 EC 020 Has no cache (also 24 bit data output as opposed to the 32 bit data output of a 68020)
68 EC 030 Has no MMU
Beyond this, ALL 68k's were planned to be engineered with FPUs. Of course.....
68 EC 040 Has no MMU and no FPU
68 LC 040 Has the MMU added, but no FPU
68 RC 040 Is the final cookie. Has it all.
68 EC 060 Like the 040, no MMU, no FPU
68 LC 060 Has MMU, but no FPU
I always go by my own personal definitions
EC = Economy LC = low class, RC = Royal Class.
heheh
You know, I read an article lately that mentioned a weakness in some 060's reguarding the FPU. Something to do with poor pipelining for the FPU circuitry.
A lot more "EC060's" were produced with the possible expectation other FPU options could be considered.
Im currently thinking about making my own A3000 CPU card and have often thought of adding a 68882 to pick up the FPU operations.
But I was planning on using a simple "LC040" + the 882.
Something like 40 mhz 040 and a 50mhz 68882.
I thought about the same for an 060, but a couple things bothered me.
1. Speed of the FPU should be equal or faster than the CPU. Motorola's own recommendations.
2. 68882 seems to be maxed out at 50mhz. Which so happens to be the minimum speed of the 060. grrr
yet another thing.
3. Most of the 060's made, all the 50mhz versions seem to have the FPU, while more 66mhz versions and 75mhz versions DONT seem to have the FPU. At least the "available" ones dont.
I can see two possible solutions to this, but both would involve doing something no one else here but me would be willing to do.
1. Remake your own 060 card, and use either a PPC's FPU, or a coldfire's internal FPU.
or
2. Remake the card, put a socket for a 68882 @50mhz in and try and find one of the latest revisions. Overclock that thing to 75 mhz or even 100mhz. Supposedly, and this is a BIG
SUPPOSEDLY, they really did make 100mhz 882's and stamped them with "50"
I read this years back about it, but I don't believe it at all unless someone proves it.
It's probably bogus, but look at it this way. If you do get that far..... you can always buy more and overclock the crap out of them until they die.
Such a practice could cause a drought of 882's in the world and they'll be forced to make more faster ones right?
All a part of my master plan. Muhahah.
So get ta overclocking them FPU's today!
Ok that's the cold medicine talking.
:-D