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Found these inside a non-working 71B
03-13-2018, 07:09 PM
Post: #65
RE: Found these inside a non-working 71B
(03-13-2018 06:19 PM)Paul Berger (Canada) Wrote:  Reading a little more about the memory configuration you could have a RAM module that contains more than 32K bytes the 64K nibble limit is for an individual chip but a module could contain more than one chip, for instance the the 4K modules used for the base memory contain four 1K byte chips, so when they are polled by the configuration routine, they report 0000E 0000E 0000E 8000E where each group of 5 characters (nibbles) represents on chip in the module the "E" indicates it is a 2K nibble chip and the "8" in the last one reported indicates it is the last chip in the module. The OS as far as freeport and claimport are concerned still treat it as a single unit of memory. For a 64K module you could have it composed of two 32K chips and it would report as 00009 80009. The last nibble in the string indicates the size and is equal to 15-log2(size in nibbles). When you run the RAM diagnostics from the diagnostic module it reports for each chip in the module.

The question isn't if ports >32k can be created. The EPROM programmer, FRAM71, and the Emu71 emulators can all be easily configured for modules >32k.

The question is can two 32k modules be configured as a single 64k port and if so, how?

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RE: Found these inside a non-working 71B - Dave Frederickson - 03-13-2018 07:09 PM
What's U10? - Dave Frederickson - 03-15-2018, 03:43 PM

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