CN1297192A - In-situ implementation method for site software of bus peripherals - Google Patents

Abstract

A method for in-situ implementing the bus-type peripheral slave site with software features that a single-chip computer is connected to bus interface and driver while to the encoding switches, the PROFIBUS-DP slave site protocol is integrated in said single-chip computer, and the program of single-chip computer is running to implement the PROFIBUS-DP protocol. Its advantages are no need of protocol ASIC and low development cost.

Description

The software implementation method of bus peripheral slave station

The invention belongs to computer field bus peripherals field, relate in particular to a kind of software implementation method of bus peripheral slave station.

At present bus peripheral slave station is the PROFIBUS-DP slave station, all adopts the specialized protocol chip, mostly is protocol chip SPC3 and SPC4 that SIEMENS makes greatly, in this protocol chip, abides by EN50170, integrated PROFIBUS-DP slave station agreement.But, adopt this kind method to realize the PROFIBUS-DP slave station, operating cost is very high.

The purpose of this invention is to provide and a kind ofly can replace the specialized protocol chip, reduce the software implementation method of the bus peripheral slave station of operating cost.

Technical scheme of the present invention is: a kind of fieldbus disperses the software implementation method of peripherals slave station, it is characterized in that:

(1) single-chip microcomputer is connected with bus interface and drive unit, simultaneously single-chip microcomputer is linked to each other with toggle switch, single-chip microcomputer is integrated bus peripheral slave station agreement, i.e. PROFIBUS-DP slave station agreement;

(2) by the program in the operation single-chip microcomputer, just can reach the function that PROFIBUS-DP realizes from station software, its concrete job step is:

1) by toggle switch tributary address is set, system powers on;

2) slave station place beginningization, for the loop-around data exchange of slave station and PROFIBUS-DP main website is prepared:

1. locate beginningization timer T0, T1 and serial ports, forbid all interruptions;

2. to diagnostic data and configuration data initialize, diagnose simultaneously, parameter setting and configuration inspection;

3. call parameters place beginning beggar's program is checked tributary address and online baud rate, finds correct baud rate;

4. diagnose again,, repeat said process if the transmission data are wrong, if the transmission data are correct, log-on data supervisory routine then;

3) log-on data supervisory routine, slave station enter the loop-around data exchange process with main website;

1. software is at first distinguished the type of main website request message, checks whether this packet issues the verification of the data of this slave station and packet and whether correct;

2. if not the data of issuing this slave station or verification and incorrect, directly withdraw from, do not handle; If above-mentioned check is correct, then carry out data processing according to different messages;

3. if SD1 class message is distinguished its function according to function code, handle respectively; If SD2 class message is then distinguished the main website requested service according to the purpose service access point, handle respectively.

Principle of work of the present invention is: the software of PROFIBUS-DP slave station is realized, does not adopt protocol chip, but adopts software mode, in single-chip microcomputer, the all accord of integrated PROFIBUS-DP slave station can be realized the function at slave station station, fully can the instead of dedicated protocol chip.The core component of software is the slave station automat, and slave station is the request that passive station just responds main website, and not to the main website request msg.After slave station receives the request message of main website, analyze type of message, do corresponding data processing, on corresponding automat, walk the request of corresponding main website according to type of message.According to the slave station automat, slave station will experience diagnosis, parameter setting, configuration inspection, diagnose several stages again.If above-mentioned several steps is correct, slave station enters the loop-around data swap status with main website, otherwise, repeat preceding four of automat and go on foot, entirely true up to locating beginningization.

Effect of the present invention is: adopt software to realize PROFIBUS-DP slave station agreement, can replace the specialized protocol chip, therefore, can reduce cost of development, realize independent development.

The present invention is further illustrated below in conjunction with drawings and Examples.

Fig. 1 is a hardware block diagram of the present invention;

Fig. 2 is a main program flow chart of the present invention;

Fig. 3 is parameter of the present invention place beginning beggar's program program flow diagram;

Fig. 4 is a data management subroutine flow chart of the present invention;

Among Fig. 1,8051 single-chip microcomputers 1 are connected with bus interface and drive unit 2, simultaneously single-chip microcomputer 1 is linked to each other with toggle switch 3, bus interface and drive unit 2 link to each other with main website 4, single-chip microcomputer 1, bus interface and drive unit 2 and toggle switch 3 have constituted slave station module 5, single-chip microcomputer 1 is integrated bus peripheral slave station agreement, i.e. PROFIBUS-DP slave station agreement, program by in the operation single-chip microcomputer just can reach the function that PROFIBUS-DP realizes from station software.

Among Fig. 2, master routine is at first located beginningization timer T0, T1 and serial ports, forbids all interruptions, then to diagnostic data and configuration data initialize, diagnoses simultaneously, parameter setting and configuration inspection; Call parameters place beginning beggar's program is checked tributary address and online baud rate then, finds correct baud rate; Diagnose again,, repeat said process if the transmission data are wrong, if the transmission data are correct, log-on data supervisory routine then; Log-on data supervisory routine, slave station enter the loop-around data exchange process with main website.

Among Fig. 3, the respective value when at first being 500kbps to timer tax transfer rate is carried out the baud rate inspection, if baud rate is correct, then carries out bus and monitors, opens interruption, returns master routine then; If it is incorrect that baud kills, respective value when then being 187.5kbps to timer tax transfer rate, proceeding the baud rate inspection, is to return master routine according to result's decision of checking, still proceeds the baud rate inspection, if baud rate is correct, then return master routine, otherwise, then proceed the baud rate inspection, be performed until and find correct baud rate, seek scope is from 500kbps to 9.6kbps.

Among Fig. 4, software is at first distinguished the type of main website request message, checks whether this packet issues the verification of the data of this slave station and packet and whether correct; If not the data of issuing this slave station or verification and incorrect, directly withdraw from, do not handle; If above-mentioned check is correct, then carry out data processing according to different messages; If SD1 class message, then further check the point of destination address D A whether the station address TS-NR by the toggle switch setting equals to comprise in the message, if the result is not equal to: continue to check type of message then return, if the result equals, then further judge check code CRC correctness, if CRC is incorrect, then return and continue to check type of message, if CRC is correct, then distinguish its function, handle respectively, if func=9. then answer fieldbus data link layer FDL state and return according to function code func, if func=12 or func=13 then further check the main website whether main website is crossed this slave station parametrization; If, then carry out exchanges data, if not, master routine then returned.

If SD2 class message has then further judged whether address extension, if address extension is arranged, then get DA, judge further then whether CRC is correct, if CRC is correct, then distinguish the main website requested service according to purpose service access point DSAP; If CRC is incorrect, then return master routine; If there is not address extension, then getting DA and DSAP, if judge further then whether CRC is correct. CRC is correct, then distinguishes the main website requested service according to purpose service access point DSAP; If CRC is incorrect, then return master routine.Purpose service access point DSAP has represented different service types, DSAP=60, expression diagnosis slave station service (Diag-slave), DASP=61, expression is provided with parameter service (Set-Prm), DSAP=62, configuration service (Chk-Cfg) is checked in expression, DSAP=59, expression request slave station configuration data service (Get-cfg), DSAP=56, slave station input data, services (Rd-Inp) is read in expression.

Claims (1)

1, a kind of fieldbus disperses the software implementation method of peripherals slave station, it is characterized in that:

(1) single-chip microcomputer is connected with bus interface and drive unit, simultaneously single-chip microcomputer is linked to each other with toggle switch, single-chip microcomputer is integrated bus peripheral slave station agreement, i.e. PROFIBUS-DP slave station agreement;

(2) by the program in the operation single-chip microcomputer, just can reach the function that PROFIBUS-DP realizes from station software, its concrete job step is:

1) by toggle switch tributary address is set, system powers on;

2) slave station place beginningization, for the loop-around data exchange of slave station and PROFIBUS-DP main website is prepared:

1. locate beginningization timer T0, T1 and serial ports, forbid all interruptions;

2. to diagnostic data and configuration data initialize, diagnose simultaneously, parameter setting and configuration inspection;

3. call parameters place beginning beggar's program is checked tributary address and online baud rate, finds correct baud rate;

4. diagnose again,, repeat said process if the transmission data are wrong, if the transmission data are correct, log-on data supervisory routine then;

3) log-on data supervisory routine, slave station enter the loop-around data exchange process with main website;

1. software is at first distinguished the type of main website request message, checks whether this packet issues the verification of the data of this slave station and packet and whether correct;

2. if not the data of issuing this slave station or verification and incorrect, directly withdraw from, do not handle; If above-mentioned check is correct, then carry out data processing according to different messages;

3. if SD1 class message is distinguished its function according to function code, handle respectively; If SD2 class message is then distinguished the main website requested service according to the purpose service access point, handle respectively.

Images