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This makes the code pretty easily portable to other architectures if someone wants to make a more modern SIMM programmer. I also was pretty careful to split responsibilities of the different components and give the existing components better names. I'm pretty happy with the organization of the code now. As part of this change I have also heavily optimized the code. In particular, the read and write cycle routines are very important to the overall performance of the programmer. In these routines I had to make some tradeoffs of code performance versus prettiness, but the overall result is much faster programming. Some of these performance changes are the result of what I discovered when I upgraded my AVR compiler. I discovered that it is smarter at looking at 32-bit variables when I use a union instead of bitwise operations. I also shaved off more CPU cycles by carefully making a few small tweaks. I added a bypass for the "program only some chips" mask, because it was adding unnecessary CPU cycles for a feature that is rarely used. I removed the verification feature from the write routine, because we can always verify the data after the write chunk is complete, which is more efficient. I also added assumptions about the initial/final state of the CS/OE/WE pins, which allowed me to remove more valuable CPU cycles from the read/write cycle routines. There are also a few enormous performance optimizations I should have done a long time ago: 1) The code was only handling one received byte per main loop iteration. Reading every byte available cut nearly a minute off of the 8 MB programming time. 2) The code wasn't taking advantage of the faster programming command available in the chips used on the 8 MB SIMM. The end result of all of these optimizations is I have programming time of the 8 MB SIMM down to 3:31 (it used to be 8:43). Another minor issue I fixed: the Micron SIMM chip identification wasn't working properly. It was outputting the manufacturer ID again instead of the device ID.
23 lines
981 B
Plaintext
23 lines
981 B
Plaintext
/** \file
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*
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* This file contains special DoxyGen information for the generation of the main page and other special
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* documentation pages. It is not a project source file.
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*/
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/**
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* \page Page_LicenseInfo Source Code License
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*
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* The LUFA library is currently released under the MIT license, included below.
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*
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* Commercial entities can opt out of the public disclosure clause in this license
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* for a one-time US$1500 payment. This provides a non-exclusive modified MIT licensed which
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* allows for the free use of the LUFA library, bootloaders and (where the sole copyright
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* is attributed to Dean Camera) demos without public disclosure within an organization, in
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* addition to three free hours of consultation with the library author, and priority support.
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* Please visit the Commercial License link on \ref Page_Resources for more information on
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* ordering a commercial license for your company.
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*
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* \verbinclude License.txt
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*/
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