60 lines
1.6 KiB
C++
60 lines
1.6 KiB
C++
/*
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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collection of bitwise and array-wise operations.
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*/
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#include "bitwise.h"
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void loadUint(uint8_t *b, uint16_t v, uint8_t bitCount, bool MSBfirst)
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{
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const uint8_t last = bitCount/8;
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// count = 32
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// last = 4
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// MSBfirst = 1;
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for (uint8_t i=0; i<last; i++) {
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const uint8_t idx = MSBfirst ? last-1-i : i;
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// idx = 4-1-0
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b[i] = v >> (8*idx);
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}
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}
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uint16_t fetchU16(const uint8_t *v, bool MSBfirst)
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{
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if (MSBfirst) {
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return v[1] | (v[0]<<8);
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}
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return v[0] | (v[1]<<8);
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}
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uint32_t fetchU24(const uint8_t *v, bool MSBfirst)
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{
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if (MSBfirst) {
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return v[2] | (v[1]<<8) | (v[0]<<16);
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}
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return v[0] | (v[1]<<8) | (v[2]<<16);
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}
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uint32_t fetchU32(const uint8_t *v, bool MSBfirst)
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{
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if (MSBfirst) {
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return v[3] | (v[2]<<8) | (v[1]<<16) | (v[0]<<24);
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}
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return v[0] | (v[1]<<8) | (v[2]<<16) | (v[3]<<24);
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}
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