g.mccormick
Lifetime Supporting Member
I am just getting information about a need that a site has.
They currently have a machine that has a ML1200 and is being interfaced to by a WindowsPC running a LabView program of some sorts. Their customer is demanding that the data be read/logged at 10hz (100ms). The original equipment manufacturer says it can't be done.
So, we are looking at replacing the LabView PC with a Linux PC running our DAQ software. I will either be replacing the ML1200 with Opto22 Snapio IO, or if I can get the data rates needed, I would just keep the ML1200 in place as intellegent IO (and with enough code in place to atleast take over and safely shutdown the machine if the comms drops out).
I have never use AB before, what I konw is the the project (I have a PDF of current project), is configured for:
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Edit Resource/Owner Timeout: 60
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Passthru Link ID: 1
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Write Protected: No
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Comms Servicing Selection: No
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Message Servicing Selection: No
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave 1st AWA Append Character: \d
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave 2nd AWA Append Character: \a
Node : 1 (decimal)
Baud: 19200
Parity: NONE
File Number for Coils: 0
File Number for Contacts: 0
File Number for Input Registers: 0
File Number for Holding Registers: 7
Expanded: No
Control Line : No Handshaking
InterCharacter Timeout(x1 ms): 0
Pre Transmit Delay(x1 ms): 0
The IO is:
0 Bul.1762 MicroLogix 1200 Series C (1 or 2 C
1 1762-OF4 4-Channel Analog I/V Output Module
2 1762-IF4 Analog 4 Chan. Input
3 1762-IF4 Analog 4 Chan. Input
4 1762-IT4 4-Channel Thermocouple Input Module
5 1762-IT4 4-Channel Thermocouple Input Module
I need to look through the programming better but assuming the N7 data files that I would need to read/write are:
(5modules * 4 channels)=20 words of analog IO
4 words of statuses/digital IO (I am just guessing)
So I would estimate(ie. SWAG) that I may need 24 words of data read and perhaps 6 written.
If I program all of the data that needs to be read/written nto continuous registers, that would mean 1 read/write command.
Should I be able to get equal to or better than 10hz data throughput at 19200 baud?
They currently have a machine that has a ML1200 and is being interfaced to by a WindowsPC running a LabView program of some sorts. Their customer is demanding that the data be read/logged at 10hz (100ms). The original equipment manufacturer says it can't be done.
So, we are looking at replacing the LabView PC with a Linux PC running our DAQ software. I will either be replacing the ML1200 with Opto22 Snapio IO, or if I can get the data rates needed, I would just keep the ML1200 in place as intellegent IO (and with enough code in place to atleast take over and safely shutdown the machine if the comms drops out).
I have never use AB before, what I konw is the the project (I have a PDF of current project), is configured for:
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Edit Resource/Owner Timeout: 60
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Passthru Link ID: 1
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Write Protected: No
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Comms Servicing Selection: No
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave Message Servicing Selection: No
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave 1st AWA Append Character: \d
CHANNEL 0 (SYSTEM) - Driver: Modbus RTU Slave 2nd AWA Append Character: \a
Node : 1 (decimal)
Baud: 19200
Parity: NONE
File Number for Coils: 0
File Number for Contacts: 0
File Number for Input Registers: 0
File Number for Holding Registers: 7
Expanded: No
Control Line : No Handshaking
InterCharacter Timeout(x1 ms): 0
Pre Transmit Delay(x1 ms): 0
The IO is:
0 Bul.1762 MicroLogix 1200 Series C (1 or 2 C
1 1762-OF4 4-Channel Analog I/V Output Module
2 1762-IF4 Analog 4 Chan. Input
3 1762-IF4 Analog 4 Chan. Input
4 1762-IT4 4-Channel Thermocouple Input Module
5 1762-IT4 4-Channel Thermocouple Input Module
I need to look through the programming better but assuming the N7 data files that I would need to read/write are:
(5modules * 4 channels)=20 words of analog IO
4 words of statuses/digital IO (I am just guessing)
So I would estimate(ie. SWAG) that I may need 24 words of data read and perhaps 6 written.
If I program all of the data that needs to be read/written nto continuous registers, that would mean 1 read/write command.
Should I be able to get equal to or better than 10hz data throughput at 19200 baud?