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7425af761a
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.
81 lines
2.4 KiB
C
81 lines
2.4 KiB
C
/*
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LUFA Library
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Copyright (C) Dean Camera, 2012.
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dean [at] fourwalledcubicle [dot] com
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www.lufa-lib.org
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*/
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/*
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Copyright 2012 Dean Camera (dean [at] fourwalledcubicle [dot] com)
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Permission to use, copy, modify, distribute, and sell this
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software and its documentation for any purpose is hereby granted
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without fee, provided that the above copyright notice appear in
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all copies and that both that the copyright notice and this
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permission notice and warranty disclaimer appear in supporting
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documentation, and that the name of the author not be used in
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advertising or publicity pertaining to distribution of the
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software without specific, written prior permission.
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The author disclaim all warranties with regard to this
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software, including all implied warranties of merchantability
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and fitness. In no event shall the author be liable for any
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special, indirect or consequential damages or any damages
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whatsoever resulting from loss of use, data or profits, whether
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in an action of contract, negligence or other tortious action,
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arising out of or in connection with the use or performance of
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this software.
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*/
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/** \file
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* \brief Common USB OTG definitions for all architectures.
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* \copydetails Group_OTG
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*
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* \note This file should not be included directly. It is automatically included as needed by the USB driver
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* dispatch header located in LUFA/Drivers/USB/USB.h.
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*/
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/** \ingroup Group_USB
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* \defgroup Group_OTG USB On The Go (OTG) Management
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* \brief USB OTG management definitions.
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*
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* This module contains macros for embedded USB hosts with dual role On The Go capabilities, for managing role
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* exchange. OTG is a way for two USB dual role devices to talk to one another directly without fixed device/host
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* roles.
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*
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* @{
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*/
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#ifndef __USBOTG_H__
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#define __USBOTG_H__
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/* Includes: */
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#include "../../../Common/Common.h"
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#include "USBMode.h"
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/* Enable C linkage for C++ Compilers: */
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#if defined(__cplusplus)
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extern "C" {
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#endif
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/* Preprocessor Checks: */
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#if !defined(__INCLUDE_FROM_USB_DRIVER)
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#error Do not include this file directly. Include LUFA/Drivers/USB/USB.h instead.
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#endif
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/* Architecture Includes: */
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#if (ARCH == ARCH_AVR8)
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#include "AVR8/OTG_AVR8.h"
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#endif
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/* Disable C linkage for C++ Compilers: */
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#if defined(__cplusplus)
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}
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#endif
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#endif
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/** @} */
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