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More work with decoding and regenerating P25.

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This commit is contained in:
Jonathan Naylor
2016-09-13 18:27:50 +01:00
parent 30467a749c
commit 0dc1f1bdad
22 changed files with 442 additions and 156 deletions
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216
P25Data.cpp
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@@ -17,6 +17,10 @@
*/
#include "P25Data.h"
#include "P25Defines.h"
#include "P25Utils.h"
#include "Hamming.h"
#include "Utils.h"
#include "Log.h"
const unsigned char BIT_MASK_TABLE[] = { 0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U };
@@ -37,96 +41,130 @@ CP25Data::~CP25Data()
void CP25Data::processHeader(unsigned char* data)
{
unsigned char raw[81U];
CP25Utils::decode(data, raw, 114U, 780U);
CUtils::dump(1U, "P25, raw header", raw, 81U);
// XXX Need to add FEC code
}
void CP25Data::processLDU1(unsigned char* data)
{
// XXX No FEC done yet
bool b[24U];
b[7U] = READ_BIT(data, 411U);
b[6U] = READ_BIT(data, 410U);
b[5U] = READ_BIT(data, 413U);
b[4U] = READ_BIT(data, 412U);
b[3U] = READ_BIT(data, 415U);
b[2U] = READ_BIT(data, 414U);
b[1U] = READ_BIT(data, 421U);
b[0U] = READ_BIT(data, 420U);
unsigned char rs[18U];
unsigned char format = 0U;
unsigned char mult = 1U;
for (unsigned int i = 0U; i < 8U; i++, mult <<= 1)
format += b[i] ? mult : 0U;
unsigned char raw[5U];
CP25Utils::decode(data, raw, 410U, 452U);
decodeLDUHamming(raw, rs + 0U);
LogDebug("P25, LC_format = $%02X", format);
CP25Utils::decode(data, raw, 600U, 640U);
decodeLDUHamming(raw, rs + 3U);
if (format == 0x03U) {
LogDebug("P25, non talk group destination");
m_group = false;
} else {
m_group = true;
CP25Utils::decode(data, raw, 788U, 830U);
decodeLDUHamming(raw, rs + 6U);
b[15U] = READ_BIT(data, 613U); // 39
b[14U] = READ_BIT(data, 612U);
b[13U] = READ_BIT(data, 615U); // 37
b[12U] = READ_BIT(data, 614U);
b[11U] = READ_BIT(data, 621U); // 35
b[10U] = READ_BIT(data, 620U);
b[9U] = READ_BIT(data, 623U); // 33
b[8U] = READ_BIT(data, 622U);
b[7U] = READ_BIT(data, 625U); // 31
b[6U] = READ_BIT(data, 624U);
b[5U] = READ_BIT(data, 631U); // 29
b[4U] = READ_BIT(data, 630U);
b[3U] = READ_BIT(data, 633U); // 27
b[2U] = READ_BIT(data, 632U);
b[1U] = READ_BIT(data, 635U);
b[0U] = READ_BIT(data, 634U); // 24
CP25Utils::decode(data, raw, 978U, 1020U);
decodeLDUHamming(raw, rs + 9U);
mult = 1U;
for (unsigned int i = 0U; i < 16U; i++, mult <<= 1)
m_dest += b[i] ? mult : 0U;
CP25Utils::decode(data, raw, 1168U, 1208U);
decodeLDUHamming(raw, rs + 12U);
LogDebug("P25, TG ID = %u", m_dest);
CP25Utils::decode(data, raw, 1356U, 1398U);
decodeLDUHamming(raw, rs + 15U);
CUtils::dump(1U, "P25, LDU1 Data after Hamming", rs, 18U);
switch (rs[0U]) {
case P25_LCF_GROUP:
m_dest = (rs[4U] << 8) + rs[5U];
m_source = (rs[6U] << 16) + (rs[7U] << 8) + rs[8U];
m_group = true;
break;
case P25_LCF_PRIVATE:
m_dest = (rs[3U] << 16) + (rs[4U] << 8) + rs[5U];
m_source = (rs[6U] << 16) + (rs[7U] << 8) + rs[8U];
m_group = false;
break;
default:
LogMessage("P25, unknown LCF value in LDU1 - $%02X", rs[0U]);
break;
}
b[23U] = READ_BIT(data, 789U);
b[22U] = READ_BIT(data, 788U);
b[21U] = READ_BIT(data, 793U);
b[20U] = READ_BIT(data, 792U);
b[19U] = READ_BIT(data, 795U);
b[18U] = READ_BIT(data, 794U);
b[17U] = READ_BIT(data, 801U);
b[16U] = READ_BIT(data, 800U);
b[15U] = READ_BIT(data, 803U);
b[14U] = READ_BIT(data, 802U);
b[13U] = READ_BIT(data, 805U);
b[12U] = READ_BIT(data, 804U);
b[11U] = READ_BIT(data, 811U);
b[10U] = READ_BIT(data, 810U);
b[9U] = READ_BIT(data, 813U);
b[8U] = READ_BIT(data, 812U);
b[7U] = READ_BIT(data, 815U);
b[6U] = READ_BIT(data, 814U);
b[5U] = READ_BIT(data, 821U);
b[4U] = READ_BIT(data, 820U);
b[3U] = READ_BIT(data, 823U);
b[2U] = READ_BIT(data, 822U);
b[1U] = READ_BIT(data, 825U);
b[0U] = READ_BIT(data, 824U);
// XXX Need to add FEC code
mult = 1U;
for (unsigned int i = 0U; i < 24U; i++, mult <<= 1)
m_source += b[i] ? mult : 0U;
encodeLDUHamming(raw, rs + 0U);
CP25Utils::encode(raw, data, 410U, 452U);
LogDebug("P25, SRC ID = %u", m_source);
encodeLDUHamming(raw, rs + 3U);
CP25Utils::encode(raw, data, 600U, 640U);
encodeLDUHamming(raw, rs + 6U);
CP25Utils::encode(raw, data, 788U, 830U);
encodeLDUHamming(raw, rs + 9U);
CP25Utils::encode(raw, data, 978U, 1020U);
encodeLDUHamming(raw, rs + 12U);
CP25Utils::encode(raw, data, 1168U, 1208U);
encodeLDUHamming(raw, rs + 15U);
CP25Utils::encode(raw, data, 1356U, 1398U);
}
void CP25Data::processLDU2(unsigned char* data)
{
unsigned char rs[18U];
unsigned char raw[5U];
CP25Utils::decode(data, raw, 410U, 452U);
decodeLDUHamming(raw, rs + 0U);
CP25Utils::decode(data, raw, 600U, 640U);
decodeLDUHamming(raw, rs + 3U);
CP25Utils::decode(data, raw, 788U, 830U);
decodeLDUHamming(raw, rs + 6U);
CP25Utils::decode(data, raw, 978U, 1020U);
decodeLDUHamming(raw, rs + 9U);
CP25Utils::decode(data, raw, 1168U, 1208U);
decodeLDUHamming(raw, rs + 12U);
CP25Utils::decode(data, raw, 1356U, 1398U);
decodeLDUHamming(raw, rs + 15U);
CUtils::dump(1U, "P25, LDU2 Data after Hamming", rs, 18U);
// XXX Need to add FEC code
encodeLDUHamming(raw, rs + 0U);
CP25Utils::encode(raw, data, 410U, 452U);
encodeLDUHamming(raw, rs + 3U);
CP25Utils::encode(raw, data, 600U, 640U);
encodeLDUHamming(raw, rs + 6U);
CP25Utils::encode(raw, data, 788U, 830U);
encodeLDUHamming(raw, rs + 9U);
CP25Utils::encode(raw, data, 978U, 1020U);
encodeLDUHamming(raw, rs + 12U);
CP25Utils::encode(raw, data, 1168U, 1208U);
encodeLDUHamming(raw, rs + 15U);
CP25Utils::encode(raw, data, 1356U, 1398U);
}
void CP25Data::processTerminator(unsigned char* data)
{
unsigned char raw[36U];
CP25Utils::decode(data, raw, 114U, 210U);
CUtils::dump(1U, "P25, raw terminator", raw, 36U);
// XXX Need to add FEC code, or do we?
}
unsigned int CP25Data::getSource() const
@@ -149,3 +187,45 @@ void CP25Data::reset()
m_source = 0U;
m_dest = 0U;
}
void CP25Data::decodeLDUHamming(const unsigned char* data, unsigned char* raw)
{
unsigned int n = 0U;
unsigned int m = 0U;
for (unsigned int i = 0U; i < 4U; i++) {
bool hamming[10U];
for (unsigned int j = 0U; j < 10U; j++) {
hamming[j] = READ_BIT(data, n);
n++;
}
CHamming::decode1063(hamming);
for (unsigned int j = 0U; j < 6U; j++) {
WRITE_BIT(raw, m, hamming[j]);
m++;
}
}
}
void CP25Data::encodeLDUHamming(unsigned char* data, const unsigned char* raw)
{
unsigned int n = 0U;
unsigned int m = 0U;
for (unsigned int i = 0U; i < 4U; i++) {
bool hamming[10U];
for (unsigned int j = 0U; j < 6U; j++) {
hamming[j] = READ_BIT(raw, m);
m++;
}
CHamming::encode1063(hamming);
for (unsigned int j = 0U; j < 10U; j++) {
WRITE_BIT(data, n, hamming[j]);
n++;
}
}
}