Mega Midget Racer Issues

[curtis]

Well, finally got the MMR in and have been playing with it.

First problem, the DRAM board fails!  This occurs both when the kipper2 RAM board is installed and when it's not.  No matter what I do, DRAM fails.

Second, Sysinfo doesn't seem overly impressed.  I run Sysinfo and it doesn't show much of a speed improvement.  cpu is a 68030 20MHz.  Sysinfo shows just a little speed increase over a stock A500.

I'm thinking I'm losing a lot of the advantage of the MMR with the dead RAM board.  It's the ZIP version so all the chips are pre-soldered in, so not a whole lot I can do there.

Any suggestions from anyone?

[curtis]

For what it's worth, I just went back to the ebay auction and looked at the pictures.

According to the pics, the SRAM was installed when they took the pics.  When I got it, no.

Given that, I've requested a refund for the seller.

Caveat emptor when dealing with computer_preservation .

It would appear they're not above a little mis-describing their products.

[curtis]

Well, heck.

I need to walk back some of my remarks.

1.  It's amazing how much better the DRAM works when  clock speed is included in the parameters for firing the whole mess up!  Ditto the cpu!

2.  Contacted the seller and they admitted it was an oversight and are sending the SRAM chips out.  Only question now is why did they remove them in the first place?

Now to get the cpu "stack" balanced a little better.  That Mega Midget Racer isn't so midget!  It overhangs everything!  Perhaps a couple of nylon screws to help prop it up.

BTW, it is co-existing quite nicely with an 8MB kipper2 memory expansion and a 2MB chip RAM upgrade!

Now i just need to pick up a trapdoor memory expansion to fill that hole!

[curtis]

Well, the MMR needs a program setting the parameters in the startup-sequence to let the system know what is going on.

I entered csa-mmr dram 33 where csa-mmr is the configuration program, dram tells it what (other than the cpu) to configure and 33 the speed to clock it at.

Once I get the SRAM in I'll add SRAM and if I want to load the kickstart into the sRAM, the full statement will be

csa-mmr srom sram dram 33

BTW, you're right about the MMR not being dramatically faster without the configuration.

As far as pulling the SRAM, I almost didn't catch it!  Just happened to  look at the auction again to confirm he had verified the DRAM and lo and  behold the SRAM was in the picture.

Now to see how long it takes to get it sent from Florida to Texas...

I don't understand what you are talking about. Have you managed to get the DRAM working? What did you do?

Without DRAM and static RAM then the MMR won't be dramatically faster than an a500, because it's having to slow down to 7mhz all the time to access RAM.

What he probably means is he forgot he took the photo before he took out the static ram, because he was going to use it in something else or sell it separately. Or maybe it didn't sell for as much as he thought it would and wanted to make up for it by selling the static ram.

[curtis]

I missed that.

And I was thinking about finding a 50MHz unit and plugging it in along with the appropriate crystal.

Guess I"ll save my money!

Just went and looked up the manual for the MMR.  I was mildly curious what would happen if you put a different clock speed value in there.  For example, "100".  Dang, it looks like 33.33 is the highest it will accept.  :lol:

[curtis]

Seller sent the SRAM chips.

Popped them in and it really does make a difference in the feel of the speed.  SysInfo doesn't show any improvement, but still feels quicker.