fayette@halibut.nosc.mil (Daniel F. Fayette) (03/15/90)
Two questions: 1. I have inherited a Z-415B Add-on Memory Board which is now installed in my Z-248. The question is, can I do anything with this other than making it a large RAM drive? I do not have a Z-405 (512K to 1.1M) card. I only have 512K of system memory. Can I use the Z-415B to get 640K of system memory? How about expanded memory that can be managed by EMM.SYS? 2. Can DOS do anything with the COM3 port on the Z-248? Thanks.
cse0421@desire.wright.edu (03/15/90)
In article <2009@nosc.NOSC.MIL>, fayette@halibut.nosc.mil (Daniel F. Fayette) writes: > Two questions: > > 1. I have inherited a Z-415B Add-on Memory Board which is now installed > in my Z-248. The question is, can I do anything with this other than > making it a large RAM drive? I do not have a Z-405 (512K to 1.1M) card. > I only have 512K of system memory. Can I use the Z-415B to get 640K of > system memory? How about expanded memory that can be managed by EMM.SYS? > > 2. Can DOS do anything with the COM3 port on the Z-248? > > Thanks. Without a 405 card the 415 is not useable in a 248. The way it is set up There must be a 405 card in the machine to fill the memory up to that point. It can't be used to fill out to 640k either. Zenith made basically 3 memory cards for the 248, the 405, 415 and 445 cards. All three boards will not do EMS memory. The 405 and 415 are more restricted than the 445. They can't be addressed as many ways. The way the 445 was set up you could use it either to fill out to 640k and then add additional memory or you could use all of it as extended memory depending on how you set the jumpers. Zenith has discontinued these boards and replaced them with some new lower cost boards. I don't remember the part numbers. As for COM3 port. If you are talking about the one that the government received in the 248's then there is very little software that will see the card. Most of that software was either written by or for the government. On the other hand most any internal modem can be set COM3. And most newer communication software can see those ports. John Wolf CSE0421@desire.wright.edu
easton@zds-oem.UUCP (Jeff Easton) (03/18/90)
In article <2009@nosc.NOSC.MIL>, fayette@halibut.nosc.mil (Daniel F. Fayette) writes: > Two questions: > > 1. I have inherited a Z-415B Add-on Memory Board which is now installed > in my Z-248. The question is, can I do anything with this other than > making it a large RAM drive? I do not have a Z-405 (512K to 1.1M) card. > I only have 512K of system memory. Can I use the Z-415B to get 640K of > system memory? How about expanded memory that can be managed by EMM.SYS? > All three of the Z-248 memory boards used the same bare PC board. They were just populated differently. Some berg jumpers where changed, some wire straps where changed and some resistor packs were changed to make the board into any of the three versions, Z405, Z415, and Z445. To modify the board from one version to another requires that you hack on the board a little. I assume you want to be able to backfill to 640K and have 1M of extended. Send me email with the bare PCB number, its silk screened on the board and is of the form 85-xxxx-xx. Also tell me if the top row of memory chips are 4164's or 41256's (more than likely 41256's) and lastly tell me if your 248 is a commercial 0 wait state version or the goverment 1 wait state version. With that info I'll try to come up with a list of jumpers and resistor packs to move. You will need to be proficent in desoldering parts off of boards without destroying them, etc. Jeff Easton Zenith Data Systems Systems Engineer OEM Engineering easton@andrews.edu --or-- easton@zds-oem.zds.com I'd rather be Water Skiing...