#POCSAG DECODER SOFTWARE FOR WINDOWS HOW TO#
#POCSAG DECODER SOFTWARE FOR WINDOWS SERIAL#
#POCSAG DECODER SOFTWARE FOR WINDOWS CODE#

The idle codeword is a unique, reserved codeword used to take the place of an address in any frame that would not otherwise be filled with 64 bits. Each message codeword replaces an address codeword in the batch. A message codeword always starts with a 1 in bit 1, and always follows directly after the address. The structure of a message codeword is shown in Figure 3. In this combination, the frame location bits are the least-significant bits, and the address bits are the most-significant bits.

#POCSAG DECODER SOFTWARE FOR WINDOWS CODE#

The combination of the code plug's three pre-coded frame location bits and the address codeword's 18 address bits provides over two million different assignable codes. Bits 22 through 31 are the parity check bits, and bit 32 is the even parity bit. These addresses are determined by combinations of the values of bits 20 and 21 (the source identifier bits) these combinations are shown in Figure 4. Each POCSAG codeword is capable of providing address information for four different paging sources (address 1 through address 4). The pager looks at these bits to find its own unique address. An address codeword's first bit (bit 1) is always a zero. The structure of an address codeword is shown in Figure 4. The frame synchronization (FS) code is a unique reserved word that is used to identify the beginning of each batch. In order to maintain the proper batch structure, each frame is filled with two address codewords, or two idle codewords, or two message codewords, or any appropriate combination of the three codeword types.

#POCSAG DECODER SOFTWARE FOR WINDOWS HOW TO#

In following sections, we learn how to create the codewords.ДЄ batch consists of a frame synchronization code followed by 8 frames of two address codewords per frames (16 address codewords per batch). The bits are a type of codeword (Address or Message), Address/Message body, Function bits, Parity check bits, and Even Parity bit. Every codeword has 32 bits, and contains several fields. The decoder uses the preamble both to determine if the data received is a POCSAG signal, and for synchronization with the stream of data. The preamble shown in Figure 2, consists of 576 bits of an alternating 101010 pattern transmitted at a bit rate of 512, 1200, or 2400 bps. As you see, the signal contains several codewords (Synchronization, Preamble, Address, Message, and Idle). Preamble StructureДЇigure 2 shows the signal format. The frame synchronization code marks the start of the batch of codewords. Each batch comprises a 32-bit frame synchronization code, and eight 64-bit address frames of two 32-bit addresses or idle codewords each. The POCSAG code format consists of a preamble and one or more batches of codewords. The POCSAG code provides improved battery-saving capability and an increased code capacity. The POCSAG code is a synchronous paging format that allows pages to be transmitted in a single-batch structure. GeneralThe basic signaling pattern used in many pagers is a sequence of coded binary data using the Post Office Code Standardization Advisory Group (POCSAG) code.

#POCSAG DECODER SOFTWARE FOR WINDOWS SERIAL#

The modem connects to the serial port of a computer and sends the message on the air through a transmitter. I also wrote the code for sending the encoded message to the end user using a special modem. The website has many useful information for various wireless technologies including pager. I grabbed most of the information about the POCSAG protocol from Brad Dye's Paging Information Resource website. For this purpose, I used my previous article, BCH 21,31, for implementing a BCH Error Correction Code that is part of the POCSAG protocol that we are going to see in the following sections. This article is an effort for doing the same task using only software code. If you search Google for POCSAG Encoder/Decoder, you will find many devices from various companies. The pager uses a protocol named POCSAG or Post Office Code Standardization Advisory Group code. One of the popular technologies that has been used for many years, in many industries, is the pager. Every technology has its advantages and disadvantages.

We have available many communication technologies to communicate with each other.

Pocsag decoder software for windows