pocsag.c File Reference

#include <math.h>
#include <stdio.h>
#include <string.h>

Include dependency graph for pocsag.c:

Macros
#define	TRUE   1
#define	FALSE   0
#define	NOT   !
#define	AND   &&
#define	OR   ||
#define	const   static
#define	dx   int
#define	d8   unsigned char
#define	d32   unsigned long int
#define	UNDEFINED
#define	EVEN_PARITY_MASK   0x00000001
#define	ERROR_MASK   0x00000001
#define	BIT_MASK   0x80000000
#define	MAX_MSG   256 /* maximum length of message */
#define	PREAMBLE   0xaaaaaaaa /* preamble pattern */
#define	POCSAG_SYNC   0x3e4ba81b /* POCSAG sync word */
#define	CAPCODE_A   0x2a74e /* 19-bit Capcode A */
#define	CAPCODE_B   0x1d25a /* 19-bit Capcode B */
#define	MSG_MASK   0xfffff /* 20-bit data message mask */
#define	ALPHA_MASK   0x7f /* 7-bit mask for alphanumeric data */
#define	NUM_MASK   0xf /* 4-bit mask for numeric data */
#define	FUNC_MASK   0x3 /* 2-bit function code mask */
#define	BAD_BYTE   0x80 /* bad message byte (uncorrectable) */

Functions
d32	error_corr (register d32)
void	fix_bit (register char)
void	find_syndromes (void)
char	normalized_locator (void)
void	validation (void)
dx	comp32 (register d32, register d32)
d32 *	sync_find (register d32 *)
dx	addr_corr (register d32)
dx	num_proc (register dx, register d32)
dx	alpha_proc (register dx, register d32)
dx	msg_proc (register d32 *)
int	main (void)
d32	err_corr (register d32 datain)

Variables
d32	hexword
d32	parity
dx	error_code
char	s1
char	s3
const char	alpha []
const char	alpha3 []
const char	alpha_inv []
const char	roots []
d8	msg [MAX_MSG]
dx	alpha_count =0
dx	func
const d8	err_tab []
unsigned long	alpha_data []
unsigned long	numeric_data []

Macro Definition Documentation

#define ALPHA_MASK   0x7f /* 7-bit mask for alphanumeric data */

Referenced by alpha_proc().

#define AND   &&

#define BAD_BYTE   0x80 /* bad message byte (uncorrectable) */

Referenced by alpha_proc(), and num_proc().

#define BIT_MASK   0x80000000

Referenced by find_syndromes().

#define CAPCODE_A   0x2a74e /* 19-bit Capcode A */

Referenced by addr_corr(), and msg_proc().

#define CAPCODE_B   0x1d25a /* 19-bit Capcode B */

Referenced by addr_corr(), and msg_proc().

#define const   static

#define d32   unsigned long int

Referenced by addr_corr(), find_syndromes(), main(), msg_proc(), and sync_find().

#define d8   unsigned char

Referenced by addr_corr(), alpha_proc(), comp32(), and num_proc().

#define dx   int

Referenced by addr_corr(), alpha_proc(), comp32(), find_syndromes(), main(), msg_proc(), num_proc(), and sync_find().

#define ERROR_MASK   0x00000001

Referenced by fix_bit().

#define EVEN_PARITY_MASK   0x00000001

Referenced by find_syndromes().

#define FALSE   0

Referenced by addr_corr(), and msg_proc().

#define FUNC_MASK   0x3 /* 2-bit function code mask */

Referenced by addr_corr().

#define MAX_MSG   256 /* maximum length of message */

#define MSG_MASK   0xfffff /* 20-bit data message mask */

Referenced by msg_proc().

#define NOT   !

#define NUM_MASK   0xf /* 4-bit mask for numeric data */

Referenced by num_proc().

#define OR   ||

Referenced by msg_proc(), and sync_find().

#define POCSAG_SYNC   0x3e4ba81b /* POCSAG sync word */

Referenced by msg_proc(), and sync_find().

#define PREAMBLE   0xaaaaaaaa /* preamble pattern */

Referenced by sync_find().

#define TRUE   1

Referenced by addr_corr(), and msg_proc().

#define UNDEFINED

Function Documentation

dx addr_corr

(

register d32

data

)

References CAPCODE_A, CAPCODE_B, comp32(), d32, d8, dx, err_corr(), error_code, FALSE, func, FUNC_MASK, and TRUE.

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dx alpha_proc	(	register dx	i,
		register d32	codeword
	)

References alpha_count, ALPHA_MASK, BAD_BYTE, d8, dx, error_code, i, and msg.

dx comp32	(	register d32	sample,
		register d32	reference
	)

References d8, dx, err_tab, and i.

d32 err_corr

(

register d32

datain

)

References error_code, find_syndromes(), fix_bit(), hexword, normalized_locator(), parity, and s1.

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d32 error_corr

(

register

d32

)

void find_syndromes

(

void

)

References BIT_MASK, d32, dx, EVEN_PARITY_MASK, hexword, i, and parity.

void fix_bit

(

register char

eroot

)

References ERROR_MASK, and hexword.

int main

(

void

)

References alpha_count, alpha_data, d32, dx, func, msg, msg_proc(), numeric_data, and sync_find().

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dx msg_proc

(

register d32 *

dptr

)

References addr_corr(), alpha_proc(), CAPCODE_A, CAPCODE_B, comp32(), d32, dx, err_corr(), error_code, FALSE, func, i, MSG_MASK, num_proc(), OR, POCSAG_SYNC, and TRUE.

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char normalized_locator

(

void

)

References s1, and s3.

dx num_proc	(	register dx	i,
		register d32	codeword
	)

References BAD_BYTE, count, d8, dx, error_code, i, msg, and NUM_MASK.

d32* sync_find

(

register d32 *

dptr

)

References comp32(), d32, dx, OR, POCSAG_SYNC, and PREAMBLE.

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void validation

(

void

)

Variable Documentation

const char alpha[]

Initial value:

=
{
    0x01, 0x02, 0x04, 0x08, 0x10, 0x05,
        0x0A, 0x14, 0x0D, 0x1A, 0x11, 0x07,
        0x0E, 0x1C, 0x1D, 0x1F, 0x1B, 0x13,
        0x03, 0x06, 0x0C, 0x18, 0x15, 0x0F,
        0x1E, 0x19, 0x17, 0x0B, 0x16, 0x09,
        0x12
}

const char alpha3[]

Initial value:

=
{
    0x01, 0x08, 0x0A, 0x1A, 0x0E, 0x1F,
        0x03, 0x18, 0x1E, 0x0B, 0x12, 0x04,
        0x05, 0x0D, 0x07, 0x1D, 0x13, 0x0C,
        0x0F, 0x17, 0x09, 0x02, 0x10, 0x14,
        0x11, 0x1C, 0x1B, 0x06, 0x15, 0x19,
        0x16
}

dx alpha_count =0

unsigned long alpha_data[]

const char alpha_inv[]

Initial value:

=
{
    0x00, 0x00, 0x01, 0x12, 0x02, 0x05,
        0x13, 0x0B, 0x03, 0x1D, 0x06, 0x1B,
        0x14, 0x08, 0x0C, 0x17, 0x04, 0x0A,
        0x1E, 0x11, 0x07, 0x16, 0x1C, 0x1A,
        0x15, 0x19, 0x09, 0x10, 0x0D, 0x0E,
        0x18, 0x0F
}

const d8 err_tab[]

Initial value:

=



{

    0x0,0x1,0x1,0x2,0x1,0x2,0x2,0x3,0x1,0x2,0x2,0x3,0x2,0x3,0x3,0x4,
        0x1,0x2,0x2,0x3,0x2,0x3,0x3,0x4,0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,
        0x1,0x2,0x2,0x3,0x2,0x3,0x3,0x4,0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,
        0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,
        0x1,0x2,0x2,0x3,0x2,0x3,0x3,0x4,0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,
        0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,
        0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,
        0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,0x4,0x5,0x5,0x6,0x5,0x6,0x6,0x7,
        0x1,0x2,0x2,0x3,0x2,0x3,0x3,0x4,0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,
        0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,
        0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,
        0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,0x4,0x5,0x5,0x6,0x5,0x6,0x6,0x7,
        0x2,0x3,0x3,0x4,0x3,0x4,0x4,0x5,0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,
        0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,0x4,0x5,0x5,0x6,0x5,0x6,0x6,0x7,
        0x3,0x4,0x4,0x5,0x4,0x5,0x5,0x6,0x4,0x5,0x5,0x6,0x5,0x6,0x6,0x7,
        0x4,0x5,0x5,0x6,0x5,0x6,0x6,0x7,0x5,0x6,0x6,0x7,0x6,0x7,0x7,0x8

}

dx error_code

dx func

d32 hexword

d8 msg[MAX_MSG]

unsigned long numeric_data[]

d32 parity

const char roots[]

Initial value:

=
{
    0x00, 0x80, 0x03, 0x80, 0x06, 0x80,
        0x01, 0x80, 0x80, 0x07, 0x80, 0x0D,
        0x80, 0x0F, 0x80, 0x1A, 0x0C, 0x80,
        0x0B, 0x80, 0x02, 0x80, 0x08, 0x80,
        0x80, 0x09, 0x80, 0x11, 0x80, 0x04,
        0x80, 0x15
        }

char s1

char s3