CN107945430B

CN107945430B - Serial-port-based bidirectional concurrent communication method for intelligent POS machine

Info

Publication number: CN107945430B
Application number: CN201711192594.0A
Authority: CN
Inventors: 沈勇坚; 胡永刚; 王翔平
Original assignee: Dynamicode Co Ltd
Current assignee: Dynamicode Co Ltd
Priority date: 2017-11-24
Filing date: 2017-11-24
Publication date: 2021-09-14
Anticipated expiration: 2037-11-24
Also published as: CN107945430A

Abstract

The invention discloses a serial port-based bidirectional concurrent communication method for an intelligent POS machine, which independently processes data transmission and data reception by starting a receiving thread and a transmitting thread; and establishing a data sending queue and a data receiving queue, and performing data matching on the sent data and the processed data. This scheme is through setting up two threads, and two queues are handled, have solved asynchronous communication and have sent and receive the problem, improve the serial communication efficiency between APP and the safety chip based on the android system in the intelligent POS machine.

Description

Serial-port-based bidirectional concurrent communication method for intelligent POS machine

Technical Field

The invention relates to a network communication technology, in particular to a communication technology of an intelligent POS machine.

Background

Generally, an intelligent POS is based on an android system, and meanwhile, in order to ensure security, a security chip is added, and then, the transaction security of the intelligent POS is ensured through key management of the security chip.

The android system chip and the security chip generally adopt serial port communication, the communication method is that the android system initiates a command, and the security chip returns to the android system after receiving the command and completing processing. In the process, the APP in the android system keeps a blocking state all the time.

The serial port communication mode of the APP and the security chip in the intelligent POS machine based on the android system has the following problems.

1. The communication efficiency is low. In each communication process, the next instruction processing can be carried out only after the instruction returns a result. And the android system is a parallel computing system, so that a plurality of APPs can only be queued for processing. Affecting efficiency.

2. Two-way communication is not possible. Due to the blocking mode. The send and return instructions must match exactly. Thus, when the security chip detects a problem, such as: due to the safety triggering caused by safety protection, when the battery which independently supplies power to the safety chip is low in voltage and the like, the battery cannot be used, and information cannot be transmitted to the outside. This state can only be obtained by upper APP queries. Resulting in a poor user experience.

3. When the serial communication is abnormal, the first time check cannot be carried out. When serial communication is performed, the code error rate always exists. When the error condition occurs, the upper layer application processes the received return information after receiving the return information. Resulting in a processing failure.

Disclosure of Invention

Aiming at the problems of the serial port communication scheme in the existing intelligent POS machine based on the android system, a new communication scheme for the intelligent POS machine is needed to improve the communication efficiency of the intelligent POS machine.

Therefore, the invention aims to provide a serial port-based bidirectional concurrent communication method for an intelligent POS machine, which ensures the communication efficiency and the safety of the intelligent POS machine.

In order to achieve the aim, the serial port-based bidirectional concurrent communication method for the intelligent POS machine starts a receiving thread and a sending thread, and independently processes data sending and data receiving; and establishing a data sending queue and a data receiving queue, and performing data matching on the sent data and the processed data.

Further, the data to be issued is written into a sending queue by the service, a data sending thread polls and checks the sending queue, and when the data exists in the sending queue, integrity check is carried out;

after the data integrity check is completed, sending data to the security chip through the serial port, deleting the sending queue by the data sending thread after the security chip successfully receives the data, and inserting the sent data and a callback handle of subsequent processing into the receiving queue;

further, after the system acquires the data received by the security chip through the receiving thread, the system performs service processing and returns the data through the serial port; and the receiving thread retrieves the receiving queue through the unique index number of the message, and returns the data to the upper layer through the callback handle after inquiring the data.

Further, when the safety chip has active uploading information, the safety chip directly sends instruction data to an upper layer through a serial port, the system receives the data through a thread, the receiving thread determines that the safety chip is in an active state through instruction comparison, and processing is carried out through a preset uploading flow.

Further, the system provides an external subscription interface, if the corresponding service needs the corresponding uploading information, the information is subscribed through the interface, the information registration is carried out, and a callback function of the service receiving information is set; when receiving the message, checking the subscription to determine the service subscribed to the message, and returning the message through the callback function set by the service.

Further, the sending instructions are classified, so that a two-dimensional table is constructed to carry out instruction issuing control.

According to the scheme, two threads (a receiving thread and a sending thread) are arranged, and two queues (a sending queue and a receiving queue) are processed, so that the problems of sending and receiving of asynchronous communication are solved, and the serial port communication efficiency between the system-based service and the security chip in the intelligent POS machine is improved.

In addition, the instructions are classified, and the instructions which can be issued and cannot be issued are discriminated through the two-dimensional table, so that the continuity and the safety of the safety chip processing are guaranteed.

Drawings

The invention is further described below in conjunction with the appended drawings and the detailed description.

FIG. 1 is a flow diagram of APP data processing in an embodiment of the present invention;

FIG. 2 is a flow chart of serial port data transmission in an embodiment of the present invention;

fig. 3 is a flowchart of a serial port receiving data according to an embodiment of the present invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.

The scheme provides a serial port-based bidirectional concurrent communication method for an intelligent POS machine, and the problem of asynchronous communication sending and receiving is solved by setting two threads and processing two queues.

Therefore, the scheme starts the receiving thread and the sending thread to independently process data sending and data receiving without mutual interference; meanwhile, the scheme also establishes a data sending queue and a data receiving queue so as to carry out data matching on sent data and processed data, thereby realizing bidirectional concurrent communication based on the serial port.

The serial port-based bidirectional concurrent communication scheme for the intelligent POS machine has the following processing processes of data sending and data receiving.

1) Data distribution

The service in the intelligent POS machine system (such as an android system) writes data to be issued into a sending queue, a data sending thread polls and checks the sending queue, if the data exists in the sending queue, integrity check is firstly carried out, and whether the unique index number, the format and the like of the message meet the requirements or not.

And after the data integrity check is completed, sending data to the security chip through the serial port, deleting the sending queue by the data sending thread after the security chip successfully receives the data, and inserting the sent data and a callback handle of subsequent processing into the receiving queue.

2) Receiving data

In cooperation with the data processing, the security chip performs service processing after receiving the data, and returns the data to the intelligent POS machine system (such as an android system) through a serial port after the data processing is successful, wherein the returned message data comprises a unique index number of a issued message; the system acquires data returned by the security chip through a receiving thread; and the receiving thread retrieves the receiving queue through the unique index number of the message, and returns the data to the upper layer through the callback handle after inquiring the data.

In the scheme, when the safety chip has active uploading information, the safety chip directly sends instruction data to an upper layer through a serial port, the system receives the data through a thread, the receiving thread determines to be in an active state through instruction comparison (such as through message header analysis), and the processing is carried out through a preset uploading flow.

The system provides an external subscription interface, and if the corresponding APP needs corresponding uploading information, the system subscribes the information through the external subscription interface and registers the information; and setting a callback function of the APP receiving message.

Thus, when the system receives the upload message, it checks that there are APPs subscribed to the message, and returns the information through the callback function set by the APP.

By way of example, when the security chip has active information to upload, the information to upload includes:

(1) the voltage of the button cell is insufficient;

for safety requirements, the safety chip can work independently under the condition that no power is supplied externally, so that the button battery is required to be used for supplying power, and timely reminding is required when the button battery is insufficient

(2) Triggering a safety chip;

because the intelligent POS is a safety device, sensitive information such as a secret key can be deleted when a safety chip feels that potential safety hazards exist.

(3) The printing paper is out of paper.

The scheme aims at solving the problem that the follow-up instruction can not be processed when the preposed instruction is processed due to the limited processing capacity of the security chip, and ensures the continuity and the safety of the processing of the security chip by classifying the instructions and screening the issuable and un-issuable instructions through the two-dimensional table.

The method classifies the sending instructions, establishes a corresponding two-dimensional table aiming at the classified sending instructions, controls the issued instructions and the instructions to be issued through the two-dimensional table, avoids the conflict between the issued instructions and the instructions to be issued, and can control the issuing of the instructions.

For example, the present solution classifies the issue information as follows, so as to construct a two-dimensional table for instruction issue control.

1. System control instruction

The instructions include: system reset, system restart, online upgrade, equipment parameter setting, factory setting restoration and the like.

The instruction is characterized in that: after such an instruction is issued, the subsequent instruction cannot be issued. Re-initialization is required.

2. Printing system

The instructions include: text printing, picture printing, two-dimensional code printing and the like.

The instruction is characterized in that: because the resources of the security chip are limited, the printing cache is not too large, and when the previous printing instruction exists, the subsequent printing instruction can be forwarded only after the printing confirmation is finished. At the same time, card instructions cannot be processed at the time of printing for processing reasons.

3. Card processing

The instructions include: IC cards, PSAM cards, contactless cards, magnetic stripe cards, etc.

The instruction is characterized in that: only one card transaction can be generally performed. When the card processing is performed, the print processing cannot be performed.

4. Secure processing

The instructions include: encryption and decryption, random numbers, and the like.

The instruction is characterized in that: when safety processing is carried out, a safety module is used, and other safety instructions cannot be issued.

5. Information class

The instructions include: device SN, KSN, version number, etc.

The instruction is characterized in that: and acquiring the characteristic information.

After the system issues the instruction, the type and the state of the current instruction are recorded, and when data is returned, the type of the instruction is recovered. And when the next piece of processing is carried out, the current instruction type is obtained and is matched with the instruction type state which is not returned previously, so that the condition that the next piece of processing cannot be issued is determined.

By way of example, the present scheme sets up the following two-dimensional table:

	system control instruction	Printing system	Card processing	Information class	Secure processing
						System control instruction	0	0	0	0	0
Printing system	0	0	0	1	1
						Card processing	0	0	0	1	1
Information class	0	1	1	1	1
						Secure processing	0	1	1	1	1

The above serial-based bidirectional concurrent communication scheme is described below with reference to an application example.

Referring to fig. 1, it shows a flow of data processing performed by an APP running in an android system in an intelligent POS based on the serial-based bidirectional concurrent communication scheme, and as can be seen from the figure, the whole processing flow is as follows:

(1) inquiring whether the data receiving queue has data or not;

(2) if the data exists in the receiving queue, analyzing a data packet header;

(3) determining the processing type according to the analyzed data analysis packet header: 1. EMV flow processing is required; 2. registering an event; 3. data are transmitted transparently; if the EMV flow processing is needed, the step (4) is carried out; if the event is registered, the step (16) is carried out; if the data is transparent transmission data, the step (20) is carried out;

(4) checking APP ID and flow state, and determining whether conflict with current operation occurs: if yes, switching to the step (5); if not, turning to the step (8);

(5) performing conflict processing, and entering the step (8) if the conflict processing is finished; if the conflict can not be processed, the step (6) is carried out;

(6) deleting the data receiving queue;

(7) the socket returns an operation result;

(8) performing corresponding EMV flow processing;

(9) detecting whether firmware processing is required;

(10) acquiring an appointed APP ID;

(11) acquiring a packet sequence number;

(12) acquiring characteristic data;

(13) grouping serial port data packets;

(14) setting semaphore and calling back a function;

(15) sending a serial port sending queue;

(16) acquiring return data;

(17) analyzing data;

(18) taking out parameters;

(19) setting an event callback parameter;

(20) analyzing data;

(21) acquiring characteristic data and grouping serial port data packets;

(22) sending a serial port sending queue;

(23) setting semaphore and calling back a function;

(24) sending a serial port sending queue;

(25) acquiring return data;

(26) deleting the data receiving queue;

(27) the socket returns the operation result.

In cooperation with this, the flow of data transmission by the serial port is as follows (see fig. 2):

(1) detecting whether the sending queue list has data or not;

(2) obtaining the instruction type, and judging whether the instruction conflicts with the previous instruction: if yes, switching to the step (3); if not, switching to the step (4);

(3) acquiring a next APP ID instruction;

(4) sending data to the serial port;

(5) after receiving the confirmation information, deleting the data sending queue;

(6) join the receipt receiving queue.

In cooperation with the above, the flow of the serial port receiving data is as follows (see fig. 3):

(1) circularly acquiring data by the serial port;

(2) determining whether the data is actively uploaded data by the security chip: if not, the step (3) is carried out; if yes, turning to the step (8);

(3) matching the receiving queue data;

(4) determining whether the socket returns: if not, the step (5) is carried out; if yes, turning to the step (6);

(5) returning data through callback;

(6) deleting the data receiving queue;

(7) the socket returns an operation result;

(8) querying the APPs needed for this state;

(9) acquiring relevant parameters of a test APP, including communication parameters and callback parameters;

(10) data is returned via a callback.

Therefore, when the scheme is applied specifically, the problems of asynchronous communication sending and receiving can be effectively solved, and the compatibility between the processing capacity and the processing instruction of the security chip can be effectively solved.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The bidirectional concurrent communication method based on the serial port for the intelligent POS machine is characterized in that a receiving thread and a sending thread are started to send and receive data for independent processing without mutual interference; establishing a data sending queue and a data receiving queue, and performing data matching on sent data and processed data to realize serial-port-based bidirectional concurrent communication; the method comprises the following steps:

1) data distribution

Writing data to be issued into a sending queue by a service, polling and checking the sending queue by a data sending thread, and if the data exists in the sending queue, firstly carrying out integrity check, wherein the message has a unique index number and the message format meets the requirement;

2) receiving data

In cooperation with the data processing, the safety chip performs service processing after receiving the data, and returns the data to the intelligent POS machine system through the serial port after the data processing is successful, wherein the returned message data comprises the unique index number of the issued message; the system acquires data returned by the security chip through a receiving thread; and the receiving thread retrieves the receiving queue through the unique index number of the message, and returns the data to the upper layer through the callback handle after inquiring the data.

2. The serial-based bidirectional concurrent communication method according to claim 1, wherein when the security chip has active upload information, the security chip directly sends command data to an upper layer through the serial port, the system receives the data through a thread, the receiving thread determines that the security chip is in an active state for upload through command comparison, and the processing is performed through a preset upload flow.

3. The serial-based two-way concurrent communication method according to claim 2, wherein the system provides an external subscription interface, subscribes messages through the interface if corresponding services require corresponding upload information, performs message registration, and sets a callback function of service reception messages; when receiving the message, checking the subscription to determine the service subscribed to the message, and returning the message through the callback function set by the service.

4. The bidirectional concurrent communication method according to claim 1, wherein the transmission instructions are classified, a corresponding two-dimensional table is established for the classified transmission instructions, the instruction issue control is performed by the two-dimensional table, and the issued instructions and the instructions to be issued are controlled by the two-dimensional table.