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HIMEMV2 or equivillent PROM

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  • Chuck(G)
    replied
    Here are the GAL16V8 JEDEC, EQN and LOG files for anyone who wants to duplicate this. Since you'll be putting a 20-pin DIP iinto a 16-pin socket, you'll need to connect pins 8 and 10 (it's okay to include pin 9 if that makes the job easier) on the 20 pin DIP or, if you use a stacked socket, the socket. Just plug the GAL in so that pin 1 on the GAL matches pin 1 of U44 on the 5160 planar. Stick in 4 banks of 41256s and you're good to go.
    Attached Files

    Leave a comment:


  • Chuck(G)
    replied
    A couple of things occur to me.

    You could simply insert the free memory in DOS's memory allocation tables and see if anyone uses it.

    You could grab the source for a DOS RAMDisk or cache and hack it (if there's not such a product out there already) to use a user-specified block of memory.

    I suspect that it would be simple to take a copy of the source to HIMEM.SYS and alter it to tell DOS that your 192K is simply your version of an HMA (i.e. load device drivers and TSRs up there).

    Leave a comment:


  • ibmapc
    replied
    It works! Checkit3 now finds(and tests as good) 128k of "Hi RAM" in the D000h to F000h region. Now, I just need to figure out how to make use of this chunk of ram. I've been un-able to find old versions of QEMM or QRAM. I'm not sure that either of these wold work without a LIM 4 Board but I was hoping... Any ideas?

    Leave a comment:


  • ibmapc
    replied
    To anyone that might be following this thread, an update. Chuck say's that the GAL programmed to replicate the HIMEMV2 is on it's way to me by way of USPS. I'm so excited. I feel like a little kid waiting for Christmass. I have made the 16 to 20 pin adapter. Only took me two tries to get the solder job to look good. Good thing had some extra 20 pin low profile DIP sockets on hand. All that was required was soldering a jumper from pin 10 to pin 8, to provide ground, and trim the 4 extra pins down so that they won't interfere with the adjacent chip on th mother board.

    I'll give another update when I get it working.

    Have a Great Day

    Greg

    Leave a comment:


  • Chuck(G)
    replied
    Sure, it's safe. On a 16V8, pins 1-9 and 11 are dedicated inputs. Pins 12-19 can be assigned as input or output. Any unassigned output is high-impedance, as are any unassigned inputs.

    GALs are usually named by their maximum numbers of inputs and outputs. So a 16V8 can have at most 16 inputs or 8 outputs, but obviously not both (you run out of pins). A 24-pin 22V10 can have up to 10 outputs or 22 inputs.

    Leave a comment:


  • ibmapc
    replied
    PM Sent. Thanks again Chuck(G)! I Can't wait to try it out! In my previous post I mentioned that I planned to leave pin 8 on the GAL disconnected and run a jumper form pin 10 to socket connector 8 gnd. However, based on your reply, I believe that I can leave pin 8 connected so that pin 8 and 10 would be connected to ground. That would be a little easier since to make pin 8 NC I would have to either cut it off the chip or modify the socket adapter so that pin 8 would be insulated. Sorry if I'm rambling on. So what do you think. Can pin 8 be grounded safely?

    Leave a comment:


  • Chuck(G)
    replied
    Unlike regular CMOS, you can leave GAL pins open--the programming can essentially power off the circuitry associated with NC pins to save power. It really doesn't matter what you do with them. You can ground them if you like.

    I've run the simulation on the GAL and the output looks good.

    Unless you can program your own GALs and just need the JEDEC files, PM me with your address and I'll send you a programmed GAL to try out.
    Last edited by Chuck(G); November 29, 2011, 12:02 PM.

    Leave a comment:


  • ibmapc
    replied
    Great!
    If I am interpretting your pin out correctly the only pin that will not line up directly is number 10. So I should be able to leave #8 disconnected and run a jumper from # 10 on the GAL to #8 on the motherboard socket. Do I need to do any thing with the other pins that are not used(#'s 13,17,18 )? Should they be left open or grounded?

    Leave a comment:


  • Chuck(G)
    replied
    Okay, if we use the first and third tables as described above, we can come up with a GAL16V8
    with a pin setup like this:

    Code:
                                Chip diagram (DIP)
    
                                 ._____    _____.
                                 |     \__/     |
                              A6 |  1        20 | Vcc
                              A5 |  2        19 | A7
                              A4 |  3        18 | 
                              A3 |  4        17 | 
                              A0 |  5        16 | Q0
                              A1 |  6        15 | Q1
                              A2 |  7        14 | Q2
                                 |  8        13 | 
                                 |  9        12 |
                             gnd | 10        11 | 
                                 |______________|
    Note that Q3 isn't connected on the 5160 schematic and CE1, CE2 are always enabled. Rather than 4 tables, you get two, with duplicates.

    Leave a comment:


  • ibmapc
    replied
    I think we're on the same page. The "E2 JUMPER 1 to 2 ONLY" is what I had planned on using. On My motherboard e2 1-2 are connected by a soldered in wire that My Dad installed way back in the late '80s when we did the 640K mod.

    Leave a comment:


  • Chuck(G)
    replied
    I'm talking about these two:

    Code:
         BOTH JUMPERS INSTALLED
                          =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =
          Seg# >>>=====>  0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
                          =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =
         (4 banks of  0 = 9  9  9  9  B  B  B  B  D  D  D  D  F  F  F  E  = 928K
         256K chips)  1 = 9  9  9  9  B  B  B  B  D  D  D  D  E  F  F  E  = 864K
                      2 = 9  9  9  9  B  B  B  B  D  D  D  D  E  E  F  E  = 800K
                      3 = 9  9  9  9  B  B  B  B  D  D  D  D  E  F  E  E  = 800K
    
        E2 JUMPER 1 to 2 ONLY
                          =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =
          Seg# >>>=====>  0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
                          =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =
         (Up to 4     8 = 9  9  9  9  B  B  B  B  D  D  F  E  F  F  D  E  = 896K
         banks of     9 = 9  9  9  9  B  B  B  B  D  D  F  E  E  F  D  E  = 832K
         256K chips)  A = 9  9  9  9  B  B  B  B  D  D  E  E  F  F  D  E  = 832K
                      B = 9  9  9  9  B  B  B  B  D  D  E  E  E  F  D  E  = 768K
    The other two sets appear to be of limited use. Do I understand this correctly?

    Leave a comment:


  • ibmapc
    replied
    Originally posted by Chuck(G) View Post
    Just to save me a bit of work, what settings as described in the document for the new PROM are you most interested in? It would seem that the first and third are the most valuable ones.
    If you are talking about the section with this heading "E2 JUMPER 1 to 2 ONLY" when you mention the "third" setting, then that is the one that I'd be most likely to use with ;

    "SW2 4 & 3 = 11 (both open)==========> 640K plus segments D and E
    (OK with EGA and Hard Disk)"

    As I do have a hard disk(Silicon Valley Computer ADP50 adapter with 2 CF cards attached by IDE to CF adapter) and an ATI EGA Wonder.

    PS I have also considered removing the EGA Wonder and putting the CGA back in then I'd set the switches as follows;

    SW2 4 & 3 = 01 (4 closed, 3 open)===> 640K plus Segments A, D, and E
    (OK with Hard Disk but no EGA)
    Last edited by ibmapc; November 26, 2011, 08:06 PM.

    Leave a comment:


  • Chuck(G)
    replied
    Just to save me a bit of work, what settings as described in the document for the new PROM are you most interested in? It would seem that the first and third are the most valuable ones.

    Leave a comment:


  • ibmapc
    replied
    Here's the

    Leave a comment:


  • ibmapc
    replied
    Here's the

    The original u44 ROM is coming shortly

    Leave a comment:

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