From f6d56675f9f981c5464f0ca7a1fbb0162154e8c5 Mon Sep 17 00:00:00 2001 From: tmk Date: Wed, 13 May 2015 11:13:10 +0900 Subject: Squashed 'tmk_core/' changes from caca2c0..dc0e46e dc0e46e Rename LUFA to LUFA-git 3bfa7fa Remove LUFA-120730 215b764 Merge commit 'afa0f22a9299686fd88f58ce09c5b521ac917e8f' as 'protocol/lufa/LUFA' afa0f22 Squashed 'protocol/lufa/LUFA/' content from commit def7fca c0c42fa Remove submodule of LUFA 30f897d Merge commit '87ced33feb74e79c3281dda36eb6d6d153399b41' as 'protocol/usb_hid/USB_Host_Shield_2.0' 87ced33 Squashed 'protocol/usb_hid/USB_Host_Shield_2.0/' content from commit aab4a69 14f6d49 Remove submodule of USB_Host_Shield_2.0 git-subtree-dir: tmk_core git-subtree-split: dc0e46eaa4367d4e218f8816e3c117895820f07c --- protocol/lufa/LUFA-git | 1 - .../Projects/Magstripe/Lib/CircularBitBuffer.c | 115 +++++++++++++++++++++ 2 files changed, 115 insertions(+), 1 deletion(-) delete mode 160000 protocol/lufa/LUFA-git create mode 100644 protocol/lufa/LUFA-git/Projects/Magstripe/Lib/CircularBitBuffer.c (limited to 'protocol/lufa/LUFA-git/Projects/Magstripe/Lib/CircularBitBuffer.c') diff --git a/protocol/lufa/LUFA-git b/protocol/lufa/LUFA-git deleted file mode 160000 index b6c18b2a7c..0000000000 --- a/protocol/lufa/LUFA-git +++ /dev/null @@ -1 +0,0 @@ -Subproject commit b6c18b2a7c544653efbe12a1d4e8ba65e7d83c35 diff --git a/protocol/lufa/LUFA-git/Projects/Magstripe/Lib/CircularBitBuffer.c b/protocol/lufa/LUFA-git/Projects/Magstripe/Lib/CircularBitBuffer.c new file mode 100644 index 0000000000..fbd511b813 --- /dev/null +++ b/protocol/lufa/LUFA-git/Projects/Magstripe/Lib/CircularBitBuffer.c @@ -0,0 +1,115 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2014. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2010 Denver Gingerich (denver [at] ossguy [dot] com) + Copyright 2014 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + Permission to use, copy, modify, distribute, and sell this + software and its documentation for any purpose is hereby granted + without fee, provided that the above copyright notice appear in + all copies and that both that the copyright notice and this + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the + software without specific, written prior permission. + + The author disclaims all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** Circular bit buffer library. This will allow for individual bits + * to be stored in packed form inside circular buffers, to reduce + * overall RAM usage. + */ + +#include "CircularBitBuffer.h" + +/** Function to initialize or reset a bit buffer, ready for data to be stored into it. */ +void BitBuffer_Init(BitBuffer_t* const Buffer) +{ + /* Reset the number of stored bits in the buffer */ + Buffer->Elements = 0; + + /* Reset the data in and out pointer structures in the buffer to the first buffer bit */ + Buffer->In.CurrentByte = Buffer->Data; + Buffer->In.ByteMask = (1 << 0); + Buffer->Out.CurrentByte = Buffer->Data; + Buffer->Out.ByteMask = (1 << 0); +} + +/** Function to store the given bit into the given bit buffer. */ +void BitBuffer_StoreNextBit(BitBuffer_t* const Buffer, + const bool Bit) +{ + /* If the bit to store is true, set the next bit in the buffer */ + if (Bit) + *Buffer->In.CurrentByte |= Buffer->In.ByteMask; + + /* Increment the number of stored bits in the buffer counter */ + Buffer->Elements++; + + /* Check if the current buffer byte is full of stored bits */ + if (Buffer->In.ByteMask == (1 << 7)) + { + /* Check if the end of the buffer has been reached, if so reset to start of buffer, otherwise advance to next bit */ + if (Buffer->In.CurrentByte != &Buffer->Data[sizeof(Buffer->Data) - 1]) + Buffer->In.CurrentByte++; + else + Buffer->In.CurrentByte = Buffer->Data; + + /* Reset the storage bit mask in the current buffer byte to the first bit */ + Buffer->In.ByteMask = (1 << 0); + } + else + { + /* Shift the current storage bit mask to the next bit in the current byte */ + Buffer->In.ByteMask <<= 1; + } +} + +/** Function to retrieve the next bit stored in the given bit buffer. */ +bool BitBuffer_GetNextBit(BitBuffer_t* const Buffer) +{ + /* Retrieve the value of the next bit stored in the buffer */ + bool Bit = ((*Buffer->Out.CurrentByte & Buffer->Out.ByteMask) != 0); + + /* Clear the buffer bit */ + *Buffer->Out.CurrentByte &= ~Buffer->Out.ByteMask; + + /* Decrement the number of stored bits in the buffer counter */ + Buffer->Elements--; + + /* Check if the current buffer byte is empty of stored bits */ + if (Buffer->Out.ByteMask == (1 << 7)) + { + /* Check if the end of the buffer has been reached, if so reset to start of buffer, otherwise advance to next bit */ + if (Buffer->Out.CurrentByte != &Buffer->Data[sizeof(Buffer->Data) - 1]) + Buffer->Out.CurrentByte++; + else + Buffer->Out.CurrentByte = Buffer->Data; + + /* Reset the retrieval bit mask in the current buffer byte to the first bit */ + Buffer->Out.ByteMask = (1 << 0); + } + else + { + /* Shift the current retrieval bit mask to the next bit in the current byte */ + Buffer->Out.ByteMask <<= 1; + } + + /* Return the retrieved bit from the buffer */ + return Bit; +} + -- cgit v1.2.3