🚀 go-pugleaf

In article <820@ihwpt.UUCP> knudsen@ihwpt.UUCP (mike knudsen) writes:
>> I read an article in this newsgroup suggesting that it was cheaper by
>> ~$200 to upgrade a 520 to 1Meg than to buy a 1040.  My question is,
>(5) If you piggyback a 1040, you can put in 32 chips
>and go clear to 2 Meg.  Don't ask whether the MMU chip
>can handle that much.  In case you missed the Byte 1040ST
>article, the "extra" RAM chips are end-to-end with the "original"
>ones on the board.  You could add just 512K the first time.
The RAM controller will NOT handle 2 Meg using 256K chips. To try to
modify the system to do that looks quite hairy to me. On the other
hand, the Byte article stated that your could upgrate the 1040
to 4 Meg when the 1 Meg chips become affordable - just replace
the 256K chips and add an address line. The RAM controller will
handle that. It appears to me that you can to exactly the same
trick with a 520 - there is room on the board, and you would
just piggy back the same way as with the 1 Meg upgrade.
-- 
John Moore (NJ7E/XE1HDO)
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The opinions expressed here are obviously not mine, so they must be
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