EEPROM is slow, but any P1 that boots from EEPROM could support XMM by using a larger EEPROM. Some applications don't require high speed, but need more program space.
EEPROM is slow, but any P1 that boots from EEPROM could support XMM by using a larger EEPROM. Some applications don't require high speed, but need more program space.
The problem with using EEPROM is that there is usually a little more than 32K available out of the standard 64K EEPROM and that is barely enough with the XMM memory model to exceed the capacity of hub memory in CMM mode. What we really need is CMM+XMM.
There are 128KB EEPROMs available. A CMM+XMM mode might be useful. Not only would it increase the amount of code that can be stored in external memory, but it should also improve caching efficiency. The cache in hub RAM could be reduced to 4K, or maybe even 2K. Or by using an 8K cache you could store more code in the cache and reduce cache misses. The big problem with adding CMM to XMM would be that programs would run even slower.
There are 128KB EEPROMs available. A CMM+XMM mode might be useful. Not only would it increase the amount of code that can be stored in external memory, but it should also improve caching efficiency. The cache in hub RAM could be reduced to 4K, or maybe even 2K. Or by using an 8K cache you could store more code in the cache and reduce cache misses. The big problem with adding CMM to XMM would be that programs would run even slower.
Actually, the bigger problem is that the cache management code and the CMM kernel don't fit in a single COG at present.
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Does Catalina XMM use a cache? Have you heard anything from RossH lately? Does he plan to update Catalina to generate P2 code?
IIRC you can enable the use of cache (the standard one that was kicking around at the time). My project does not use cache.
The last I heard from Ross he was busy running a Guest House they bought in the country and were flat out. I very much doubt he will convert Catalina to generate P2 code.
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The last I heard from Ross he was busy running a Guest House they bought in the country and were flat out. I very much doubt he will convert Catalina to generate P2 code.