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Changes to fix the scrambler and LICH based on first RF tests.

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This commit is contained in:
Jonathan Naylor
2018-01-18 21:26:31 +00:00
parent 5291a6427c
commit 7745e9cf1d
4 changed files with 73 additions and 132 deletions
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88
NXDNControl.cpp
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@@ -22,12 +22,18 @@
#include <ctime>
const unsigned char SCRAMBLER[] = {
0x00U, 0x00U, 0x02U, 0x72U, 0xACU, 0x37U, 0xA6U, 0xE4U, 0x50U, 0xADU, 0x3FU, 0x64U, 0x96U, 0xFCU, 0x9AU, 0x99U,
0x80U, 0xC6U, 0x51U, 0xA5U, 0xFDU, 0x16U, 0x3AU, 0xCBU, 0x3CU, 0x7DU, 0xD0U, 0x6BU, 0x6EU, 0xC1U, 0x6BU, 0xEAU,
0xA0U, 0x52U, 0xBCU, 0xBBU, 0x81U, 0xCEU, 0x93U, 0xD7U, 0x51U, 0x21U, 0x9CU, 0x2FU, 0x6CU, 0xD0U, 0xEFU, 0x0FU};
0x00U, 0x09U, 0xCAU, 0xB0U, 0xDEU, 0x9BU, 0x91U, 0x42U,
0xB4U, 0xFDU, 0x92U, 0x5BU, 0xF2U, 0x6AU, 0x66U, 0x03U,
0x19U, 0x46U, 0x97U, 0xF4U, 0x58U, 0xEBU, 0x2CU, 0xF1U,
0xF7U};
// #define DUMP_NXDN
const unsigned char BIT_MASK_TABLE[] = { 0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U };
#define WRITE_BIT1(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE[(i)&7])
#define READ_BIT1(p,i) (p[(i)>>3] & BIT_MASK_TABLE[(i)&7])
CNXDNControl::CNXDNControl(unsigned int ran, unsigned int id, bool selfOnly, CNXDNNetwork* network, CDisplay* display, unsigned int timeout, bool duplex, bool remoteGateway, CNXDNLookup* lookup, CRSSIInterpolator* rssiMapper) :
m_ran(ran),
m_id(id),
@@ -118,11 +124,11 @@ bool CNXDNControl::writeModem(unsigned char *data, unsigned int len)
m_rssiCount++;
}
CUtils::dump(2U, "NXDN, raw data", data, len);
CUtils::dump(2U, "NXDN, raw data", data + 2U, NXDN_FRAME_LENGTH_BYTES);
scrambler(data + 2U);
CUtils::dump(2U, "NXDN, after descrambling", data, len);
CUtils::dump(2U, "NXDN, after descrambling", data + 2U, NXDN_FRAME_LENGTH_BYTES);
CNXDNLICH lich;
bool valid = lich.decode(data + 2U);
@@ -133,7 +139,7 @@ bool CNXDNControl::writeModem(unsigned char *data, unsigned int len)
// Stop repeater packets coming through, unless we're acting as a remote gateway
if (m_remoteGateway) {
unsigned char direction = m_lastLICH.getDirection();
if (direction != NXDN_LICH_DIRECTION_INBOUND)
if (direction == NXDN_LICH_DIRECTION_INBOUND)
return false;
} else {
unsigned char direction = m_lastLICH.getDirection();
@@ -146,41 +152,10 @@ bool CNXDNControl::writeModem(unsigned char *data, unsigned int len)
bool ret = false;
#ifdef notdef
if (usc == NXDN_LICH_USC_SACCH_NS || usc == NXDN_LICH_USC_SACCH_SS) {
switch (option) {
case NXDN_LICH_STEAL_NONE:
ret = processVCHOnly(valid, data);
break;
case NXDN_LICH_STEAL_FACCH1_1:
ret = processFACCH11(valid, data);
break;
case NXDN_LICH_STEAL_FACCH1_2:
ret = processFACCH12(valid, data);
break;
case NXDN_LICH_STEAL_FACCH:
ret = processFACCH1(valid, data);
break;
default:
break;
}
} else if (usc == NXDN_LICH_USC_UDCH) {
switch (option) {
case NXDN_LICH_STEAL_NONE:
ret = processUDCH(valid, data);
break;
case NXDN_LICH_STEAL_FACCH:
ret = processFACCH2(valid, data);
break;
default:
break;
}
}
if (usc == NXDN_LICH_USC_UDCH) {
ret = processData(option, data);
else
ret = processVoice(usc, option, data);
#endif
return ret;
}
@@ -1100,8 +1075,35 @@ void CNXDNControl::scrambler(unsigned char* data) const
{
assert(data != NULL);
for (unsigned int i = 0U; i < NXDN_FRAME_LENGTH_BYTES; i++)
data[i] ^= SCRAMBLER[i];
unsigned int offset = 0U;
for (unsigned int i = 0U; i < NXDN_FRAME_LENGTH_SYMBOLS; i++, offset += 2U) {
bool invert = READ_BIT1(SCRAMBLER, i);
if (invert) {
unsigned int offset1 = offset + 0U;
unsigned int offset2 = offset + 1U;
bool b1 = READ_BIT1(data, offset1);
bool b2 = READ_BIT1(data, offset2);
if (b1 && b2) {
// -3 to +3, 11 to 01
WRITE_BIT1(data, offset1, false);
WRITE_BIT1(data, offset2, true);
} else if (b1 && !b2) {
// -1 to +1, 10 to 00
WRITE_BIT1(data, offset1, false);
WRITE_BIT1(data, offset2, false);
} else if (!b1 && b2) {
// +3 to -3, 01 to 11
WRITE_BIT1(data, offset1, true);
WRITE_BIT1(data, offset2, true);
} else {
// +1 to -1, 00 to 10
WRITE_BIT1(data, offset1, true);
WRITE_BIT1(data, offset2, false);
}
}
}
}
bool CNXDNControl::openFile()