From 583f00e0b8efe2832f63efb478a51d3ad35e92ed Mon Sep 17 00:00:00 2001 From: Nicolas Schodet Date: Sun, 7 Oct 2007 22:16:03 +0200 Subject: Included SI2E avr modules. Well, this need more works... --- digital/avr/modules/utils/byte.h | 100 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 digital/avr/modules/utils/byte.h (limited to 'digital/avr/modules/utils/byte.h') diff --git a/digital/avr/modules/utils/byte.h b/digital/avr/modules/utils/byte.h new file mode 100644 index 00000000..436e0054 --- /dev/null +++ b/digital/avr/modules/utils/byte.h @@ -0,0 +1,100 @@ +#ifndef byte_h +#define byte_h +/* byte.h */ +/* avr.utils - Utilities AVR module. {{{ + * + * Copyright (C) 2005 Nicolas Schodet + * + * Robot APB Team/Efrei 2006. + * Web: http://assos.efrei.fr/robot/ + * Email: robot AT efrei DOT fr + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * }}} */ + +/** WARNING: Theses functions only works on little endian processor, do not + * use them on other processors, prefer the portable bit shifts and or. This + * file only exist to overide bad code production with avr-gcc in the bit + * shifts idiom. */ + +/* Union needed for byte access. */ +union _utils_byte_access +{ + uint8_t v8[4]; + uint16_t v16[2]; + uint32_t v32; +}; + +/** Byte packing macro, pack 4 bytes into a double word. */ +extern inline uint32_t +v8_to_v32 (uint8_t b3, uint8_t b2, uint8_t b1, uint8_t b0) +{ + union _utils_byte_access ba; + ba.v8[0] = b0; + ba.v8[1] = b1; + ba.v8[2] = b2; + ba.v8[3] = b3; + return ba.v32; +} + +/** Byte packing macro, pack 2 bytes into a word. */ +extern inline uint16_t +v8_to_v16 (uint8_t b1, uint8_t b0) +{ + union _utils_byte_access ba; + ba.v8[0] = b0; + ba.v8[1] = b1; + return ba.v16[0]; +} + +/** Word packing macro, pack 2 words into a double word. */ +extern inline uint32_t +v16_to_v32 (uint16_t w1, uint16_t w0) +{ + union _utils_byte_access ba; + ba.v16[0] = w0; + ba.v16[1] = w1; + return ba.v32; +} + +/** Byte unpacking macro, extract one specified byte from a double word. */ +extern inline uint8_t +v32_to_v8 (uint32_t d, int pos) +{ + union _utils_byte_access ba; + ba.v32 = d; + return ba.v8[pos]; +} + +/** Byte unpacking macro, extract one specified byte from a word. */ +extern inline uint8_t +v16_to_v8 (uint16_t w, int pos) +{ + union _utils_byte_access ba; + ba.v16[0] = w; + return ba.v8[pos]; +} + +/** Word unpacking macro, extract one specified word from a double word. */ +extern inline uint16_t +v32_to_v16 (uint32_t d, int pos) +{ + union _utils_byte_access ba; + ba.v32 = d; + return ba.v16[pos]; +} + +#endif /* byte_h */ -- cgit v1.2.3