Function description:

Management of the block XXMIT for interrogation of ten devices with different frequency of interrogation

Symbol:

____________________

| |

| CNTRL_XM |

| |

BOOL ---| Abort LstPErr |--- BOOL

BOOL ---| X_Activ LstPErrD |--- UINT

INT ---| X_Err LstPErrC |--- WORD

| Err_Cd |--- aWORD_1x10

UINT ---| iDvNmPol oDvNmPol |--- UINT

aMB_Var_1x10 ---| iVar oVar |--- aMB_Var_1x10

aUINT_1x10 ---| iOK_Cnt oOK_Cnt |--- aUINT_1x10

aUINT_1x10 ---| iErr_Cnt oErr_Cnt |--- aUINT_1x10

| X_Start |--- BOOL

UINT ---| Dev_Num X_Cmnd |--- WORD

aMB_Cnst_1x10 ---| Cnst X_MsgOut |--- aWORD_1x10

aMB_XXMIT_1x10 ---| XXMIT_PR X_MsgLen |--- INT

| X_Port |--- BYTE

| X_BR |--- INT

| X_DB |--- BYTE

| X_StpB |--- BYTE

| X_Parity |--- BYTE

| X_RespT |--- INT

| X_RtrLmt |--- INT

| X_StrtD |--- INT

| X_EndDly |--- INT

|____________________|

Parameter description:

Description of the block parameters:

Parameter Data type Meaning

Abort BOOL To interrupt interrogation

X_Activ BOOL The Block XXMIT is active

X_Err INT Code of a mistake from the block XXMIT

iDvNmPol UINT Number of the device, interrogated at the given moment

iVar aMB_Var_1x10 The Variable information

iOK_Cnt aUINT_1x10 The Counter of successful transfers of the information

iErr_Cnt aUINT_1x10 Counter of unsuccessful transfers of the information

Dev_Num UINT Quantity of devices in a network

Cnst aMB_Cnst_1x10 The Constant information on devices

XXMIT_PR aMB_XXMIT_1x10 Parameters of devices for the block XXMIT

LstPErr BOOL Last interrogation was finished with a mistake

LstPErrD UINT Number of the device, for which the interrogation was finished with a mistake

LstPErrC WORD A Code of last mistake

Err_Cd aWORD_1x10 Codes of mistakes

oDvNmPol UINT Number of the device, interrogated at the given moment

oVar aMB_Var_1x10 The Variable information

oOK_Cnt aUINT_1x10 The Counter of successful transfers of the information

oErr_Cnt aUINT_1x10 The Counter of unsuccessful transfers of the information

X_Start BOOL Start of the block XXMIT

X_Cmnd WORD Parameter for the block XXMIT

X_MsgOut aWORD_1x10 Parameter for the block XXMIT

X_MsgLen INT Parameter for the block XXMIT

X_Port BYTE Parameter for the block XXMIT

X_BR INT Parameter for the block XXMIT

X_DB BYTE Parameter for the block XXMIT

X_StpB BYTE Parameter for the block XXMIT

X_Parity BYTE Parameter for the block XXMIT

X_RespT INT Parameter for the block XXMIT

X_RtrLmt INT Parameter for the block XXMIT

X_StrtD INT Parameter for the block XXMIT

X_EndDly INT Parameter for the block XXMIT

Structure sMB_Variable.

Element of structure	Type	Description
Stat	WORD	Bit 0 = 1 - goes interrogation; Bit 1 = 1 - on the given cycle of scanning inquiry was finished without a mistake; Bit 2 = 1 - on the given cycle of scanning inquiry was finished with a mistake; Bit 3 = 1 - last inquiry was finished without a mistake; Bit 4 = 1 - last inquiry was finished with a mistake.
Prior	UINT	The priority of interrogation (0 - is not interrogated or there is an interrogation, 1 - lowest, 65535 - maximum)

Structure sMB_Constant.

Element of structure	Type	Description
Prior_Beg	UINT	The priority of interrogation exposed after download or end of interrogation of device (0 - is not interrogated, 1 - lowest, 65535 - maximum)
PriorAdd_Ok	UINT	Meaning, by which the priority of interrogation is increased everyone 10ms, if the interrogation has taken place without a mistake
PriorAdd_Err	UINT	Meaning, by which the priority of interrogation is increased everyone 10ms, if the interrogation has taken place with a mistake

Structure sMB_XXMIT_par.

Element of structure	Type	Description
Command	WORD	The carried out command (is usual 0100h for Modbus)
MsgLen	INT	Length of the message (is usual 5)
Baudrate	INT	Baudrate. Gets out of a line 50, 75, 110, 134, 150, 300, 600, 1200, 1800, 2000, 2400, 3600, 4800, 7200, 9600, 19200
Port	BYTE	Number of port (1 - for 1-st port CPU. The port 2 is accessible only for Momentum)
Databits	BYTE	Quantity bit of the data. For a mode ASCII 7, for a mode RTU 8 (it is usual 8)
Stopbits	BYTE	Quantity of stop - bit: 1 or 2. (it is usual 1)
Parity	BYTE	The control of parity (is usual 2): 0 - there is no control; 1 - odd; 2 - even.
RespTour	INT	The waiting time of the correct answer, ms
RetryLmt	INT	The number of repeated attempts before reception of the correct answer
StartDly	INT	The idle time before transfer of the message, ms
EndDly	INT	The idle time after transfer of the message, ms
MsgOut[1]	WORD	Carried out function: 1 - to read the registers such as 0x from slave; 2 - to read the registers such as 1x from slave (in area 0х); 3 - to read the registers such as 4x from slave; 4 - to read the registers such as 3x from slave (in area 4х); 5 - to write down the one register 0х in slave; 6 - to write down the one register 4х in slave; 15 - to write down the registers 0х in slave; 16 - to write down the registers 4х in slave.
MsgOut[2]	WORD	Quantity of the read or write registers
MsgOut[3]	WORD	The address of the device slave in a network
MsgOut[4]	WORD	The address of memory of the device slave, whence to read (or where to write) the data
MsgOut[5]	WORD	The address of memory of the controller where to write (or whence to read) the data

Detailed description:

It is consistently possible to interrogate up to 10 devices in a network Modbus with various frequency. The quantity of devices is stored in input Dev_Num.

For interrogation of devices the following algorithm is carried out:

1. In a cycle all devices get over and the device with the maximal priority is searched (if them it is a some, the device with a smaller serial number) gets out.

2. If the priority is not equal 0, the inquiry about the given device is given out.

3. After ending interrogation byte of the status and code of a mistake is filled.

4. For the interrogated device the given priority is exposed.

Algorithm of definition of priorities in parallel works:

1. For all devices, which are required to be interrogated and which interrogation at the given moment is not carried out, through everyone 10ms the priority is increased by the given meaning.