CompuServe Thread

#GForce 040 MMU?

4 messages in this thread
#75383From: Stephen BaileyFeb 24, 1994 3:58 PM
Dear GVP Tech: I've been trying to get Gigamem running on my system. I have an A2000 with a G-Force '040 board. My problem seems to revolve around the enabling of the '040's MMU. Using the SYSTEMinfo (i.e. GVPInfo, off the GVP disk) I have discovered that my MMU status is "inactive". I noticed in GVP manual, under jumper configurations, that J7 is to be left OPEN in order to enable the MMU. Here's where I run into trouble. The illustration in the manual shows J10, J9, J8, J7, J16, and J15 all lined up from top to bottom (near the top middle of the board). However, when I look at my actual board, there are only 5 jumpers (J10 and J15 are marked as the top and bottom jumpers on the board itself). Which one is J7? Which one is missing? Manual Illustration Actual Board Jumpers J10 J10 J9 ??? J8 ??? J7 ??? J16 J15 J15 I hope that you can atleast visualize the problem. All I'm really wondering is how to enable the MMU. I checked the '040 chip and it is NOT a 68EC040, the one which the manual says comes without an MMU. Thanks in advance for your assistance. Stephen Bailey Sawyer & Bailey Film and Video CIS # 72773,2451
#75425From: Gary NushFeb 25, 1994 6:39 AM
I don't know what jumpers are what….the GVP Tech will have better information on that. But I do know that all of the A2000 GForce040's used real, full Motorola 68040's with MMU's. The listing of "inactive" could refer to the fact that the MMU is currently not being used for anything (i.e. Kickstart remapping, memory protection, etc.). Just a thought… Gary Nush
#75438From: Stephen BaileyFeb 25, 1994 2:22 PM
Thanks for the response, Gary. I understand what you mean about the MMU possibly not being utilized when I run the GVPInfo test. However, if Gigamem won't start-up, I suspect that it cannot find (and use) the MMU, meaning that it is not enabled. Hopefully, GVP or INNOVAtronics is listening. Stephen Bailey Sawyer & Bailey Film and Video CIS # 72773,2451
#76080From: GVP TechMar 3, 1994 7:49 AM
Stephen, It will probably require an update in the GIGAMEM software at this point. There is no way to ENABLE the MMU. If one exists, then it is available to the FIRST program that attempts to use it. If the program is looking somewhere else or the MMU is being used by another program at that time, then it will fail. GVP TECH