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#KICKSTART in ROM

7 messages in this thread

#59541From: E. J. Lippert IIMar 19, 1987 6:28 AM

Larry: I still deserve the apology, but I owe you one! I mis-typed our starting address, sorry! We reside in the E9XXXXX area of the map, not the 9XXXXX area, and therefore DO NOT, as I said, use any RAM area. And, whatever the Docs say, the smallest address space a device can request is 64K. By the way, there is almost 2 Megs of space reserved up there for devices like ours, it is highly unlikely that we will run out at 64K a whack! E.J. Lippert II C Ltd. – (316) 267-6322

#59557From: John DraperMar 19, 1987 10:49 AM

Ed, Looks like I do owe you one. Sorry. I found the reference I was speaking of, but it turned out to be in the old RKM, which of course was changed later. Coincidentally, I was going to leave you a message tonight telling you that you do in fact configure at $E90000. A friend has a C. Ltd hard drive, and I did a little investigating. Regards, Larry.

#59655From: E. J. Lippert IIMar 19, 1987 11:46 PM

Larry: Thanks, Now let's explore some ways to make use of that wasted 64K. We actually only use 32 Bytes of address space at our assigned start address. There's got to be some good use for the other 65,502 bytes of fully available mapped-in addresses. Got any good ideas? E.J. Lippert II C Ltd. – (316) 267-6322

#59662From: John DraperMar 20, 1987 12:30 AM

Ed, For a start, is there any way you can use it as a buffer? I am not overly familiar with your controller, but if you could buffer, for example, the directory, flagging it changed when appropriate, and updating between operations, it might be helpful. Regards, Larry.

#59679From: E. J. Lippert IIMar 20, 1987 1:55 AM

Larry: Possibly, but that would require RAM on our board, raising the cost. We could, and do to some extent (we build a 5K RAM CACHE buffer), do that now in normal Amiga RAM. Do you think it would justify the extra expense? E.J. Lippert II C Ltd. – (316) 267-6322

#59693From: John DraperMar 20, 1987 3:59 AM

Ed, it would depend entirely on the speedup and the cost of it. Regards, Larry.

#59911From: E. J. Lippert IIMar 21, 1987 2:44 PM

Larry: The overall speed up would be generally less that moving our current controller up to a DMA type. The cost would be about the same. Cost about $100.00 at retail, Speedup in DBMS applications 5x, normal file handling 30-50%, file loading 0, file saving 0. The above speedup figures are estimates. E.J. Lippert II C Ltd. – (316) 267-6322