CN109150406B - Data packet subpackaging method for byte stream communication - Google Patents

Abstract

A data packet sub-packaging method for byte stream communication belongs to the technical field of communication. The method comprises the following steps: distinguishing a packet header; packing by a sender; and unpacking by a receiver. The method is time-saving and resource-saving.

Description

Data packet subpackaging method for byte stream communication

Technical Field

The invention belongs to the technical field of communication, and particularly relates to a data packet subpackaging method for byte stream communication.

Background

In byte stream communication, the current data packet subpackaging method has the defect of high energy consumption, and is not beneficial to resource saving.

Disclosure of Invention

In order to solve the above problems, the present invention provides a method for packetizing data packets for byte stream communication, the method comprising the steps of: distinguishing a packet header; packing by a sender; and unpacking by a receiver.

Preferably, the sender packing method includes:

the assignment of the 9 th byte of the buffer area is zero, and the bit7 of the 6-byte load (data to be sent) is filled into the bit 0-5 of the 9 th byte of the buffer area;

calculating the XOR check of 6 bytes of source load data, filling bit7 of a check code into bit6 of the 9 th byte of a sending cache, setting the bit7 of the check code to be 0 and filling the bit into the 8 th byte of a cache region;

setting bit7 of 6-byte load to 0 and then sequentially filling the bit7 into 2 nd to 7 th bytes of a buffer area;

and generating a packet header as required and then transmitting the packet header.

Preferably, the unpacking step of the receiving side includes:

step 1: when the byte of bit7 is 1 and the addresses match, the header is considered to be stored in the receiving buffer;

step 2: continuously receiving 8 bytes with bit7 being 0, storing the bytes into a cache, and if the subsequent bytes have bit7 being 1, determining that the communication is faulty and returning to the step 1;

and step 3: restoring the load and the check code by using the 9 th byte, checking the 2 nd to 7 th bytes, and returning to the step 1 if the checking fails; and (5) successfully checking to obtain the instruction of the sender.

The method of the invention can be continuously or discontinuously transmitted without time limitation; because strict time sequence control is not needed, CPU resources such as a timer can be saved; and the bandwidth utilization rate is also improved because the time delay is not needed.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to specific embodiments. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

The invention provides a data packet subpackaging method for byte stream communication, which comprises the following steps:

distinguishing a packet header; packing by a sender; and unpacking by a receiver.

For example convention (not limited to this approach): fixed-length data packets (9 bytes). It is agreed that the first bit (bit7) of each byte is a header flag bit, 1 indicates a header, and the flag bits of other data are 0.

Wrapping head

The first byte is a packet header, and the flag bit is 1; the slave enables: the values 1-4 of bits 0-3 represent drivers 1-4 respectively, 0 represents mass sending, and 5 represents a host; slave reply enable: the values of bits 4-6 indicate that the corresponding driver # 1-4 is allowed to reply to the command, and when equal to 0, no slave replies are allowed (only when the corresponding slave receives the command and the slave reply enable is equal to the slave number).

Payload data

The 2 nd to 7 th bytes are data after the source load data bit7 is set to 0.

Verification

The source payload data is in turn bitwise xored and bit7 is set to 0.

Bit7 of the first 7 bytes

Bit0 is Bit7 of the first byte of the source payload data, and … … through Bit6 in turn are Bit7 of the source parity value.

Specifically, the sender packaging method includes: the assignment of the 9 th byte of the buffer area is zero, and the bit7 of the 6-byte load (data to be sent) is filled into the bit 0-5 of the 9 th byte of the buffer area; calculating the XOR check of 6 bytes of source load data, filling bit7 of a check code into bit6 of the 9 th byte of a sending cache, setting the bit7 of the check code to be 0 and filling the bit into the 8 th byte of a cache region;

setting bit7 of 6-byte load to 0 and then sequentially filling the bit7 into 2 nd to 7 th bytes of a buffer area;

and generating a packet header as required and then transmitting the packet header.

Specifically, the unpacking step of the receiver includes:

step 1: when the byte of bit7 is 1 and the addresses match, the header is considered to be stored in the receiving buffer;

step 2: continuously receiving 8 bytes with bit7 being 0, storing the bytes into a cache, and if the subsequent bytes have bit7 being 1, determining that the communication is faulty and returning to the step 1;

and step 3: restoring the load and the check code by using the 9 th byte, checking the 2 nd to 7 th bytes, and returning to the step 1 if the checking fails; and (5) successfully checking to obtain the instruction of the sender.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations as fall within the scope and boundaries of the appended claims, or the equivalents of such scope and boundaries.

Claims (1)

1. A method for packetizing data packets for byte stream communication, the method comprising: distinguishing a packet header; packing by a sender; unpacking by a receiver;

a fixed-length data packet with 9 bytes, wherein a first bit7 of each byte is appointed as a header flag bit, 1 represents a packet header, and flag bits of other data are 0;

the sender packaging method comprises the following steps:

the assignment of the 9 th byte of the buffer area is zero, and bit7 of 6 data byte loads to be sent is filled into bit 0-5 of the 9 th byte of the buffer area; calculating the XOR check of 6 bytes of source load data, filling bit7 of a check code into bit6 of the 9 th byte of a sending cache, setting the bit7 of the check code to be 0 and filling the bit into the 8 th byte of a cache region;

setting bit7 of 6-byte load to 0 and then sequentially filling the bit7 into 2 nd to 7 th bytes of a buffer area;

generating a packet header according to the requirement and then sending the packet header;

the unpacking step of the receiver comprises the following steps:

step 1: when the byte of bit7 is 1 and the addresses match, the header is considered to be stored in the receiving buffer;

step 2: continuously receiving 8 bytes with bit7 being 0, storing the bytes into a cache, and if the subsequent bytes have bit7 being 1, determining that the communication is faulty and returning to the step 1;

and step 3: restoring the load and the check code by using the 9 th byte, checking the 2 nd to 7 th bytes, and returning to the step 1 if the checking fails; and (5) successfully checking to obtain the instruction of the sender.