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Changed to BearSSL for meter decryption on ESP8266 + some minor changes

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This commit is contained in:
Gunnar Skjold
2021-01-17 12:34:57 +01:00
parent af8f5a7c24
commit f9597c786e
345 changed files with 129 additions and 175455 deletions
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29
lib/HanReader/src/Crc16.cpp
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@@ -1,36 +1,13 @@
#include "Crc16.h"
Crc16Class::Crc16Class()
{
unsigned short value;
unsigned short temp;
for (unsigned short i = 0; i < 256; ++i)
{
value = 0;
temp = i;
for (byte j = 0; j < 8; ++j)
{
if (((value ^ temp) & 0x0001) != 0)
{
value = (ushort)((value >> 1) ^ polynomial);
}
else
{
value >>= 1;
}
temp >>= 1;
}
table[i] = value;
}
}
Crc16Class::Crc16Class() { }
unsigned short Crc16Class::ComputeChecksum(byte *data, int start, int length)
{
unsigned short Crc16Class::ComputeChecksum(byte *data, int start, int length) {
ushort fcs = 0xffff;
for (int i = start; i < (start + length); i++)
{
byte index = (fcs ^ data[i]) & 0xff;
fcs = (ushort)((fcs >> 8) ^ table[index]);
fcs = (ushort)((fcs >> 8) ^ crc16_ccitt_table_reverse[index]);
}
fcs ^= 0xffff;
return fcs;