Scanivalve MPS4232, Руководство по аппаратному и программному обеспечению

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MPS4232
Section 5: Software
MPS4200 Buffer Description
The ring buffer on the MPS4200 sits between the scan task and the binary output task. It is 32768 elements in size with each
element holding 160 bytes, making the total ring buffer 5,242,880 bytes. At 1000Hz, the MPS can buffer approximately 32.7
seconds of data (32768 / 1000). The binary output task has a lower priority than the scan task. This is necessary so that input
scan data is not missed.
The buffer is the liaison between the scan task and the scan output task. The scan output task has a higher priority than the
scan task. Under initial conditions, when the buffer is empty, the scan task places one frame of data in the buffer. It then
signals the scan output task to read the buffer until it is empty. However, when multiple frames of data are in the buffer, the
output task continues until the buffer is empty. Multiple frames of data will accumulate if the scan output task is blocked by
the network while outputting data.
MPS Network Configurations
The MPS may be configured in three basic network arrangements:
Isolated Network
The isolated MPS network provides the fastest possible data throughput because other network traffic has been eliminated.
MPS commands are issued from the network client/host and data is directed to the network client/host in user-configured
format. This configuration is ideal for high speed data transfer with data reduction that is handled by the network client/
host.
Integrated with System Network
The integrated MPS provides the most accessible data to all network clients. Any client/host on the network may control any
or all of the MPS’s. Depending on the data transfer protocol, network throughput may be reduced because of other network
traffic. This configuration is ideal for systems that can tolerate slower data transfer rates but require easy access by multiple
client/hosts to each MPS unit.
Sub-Network with Gateway
The MPS sub-network allows high speed data transfer of the sub-network while allowing access by a larger network. The
gateway is most effective as a multi-homed client/host that can store the MPS data for later access by client/hosts on the
main system network.
MPS Data Output Definitions
When requested the MPS sends an application packet to the client. Each packet sent to the client starts with a Packet Type
Word. This word defines the packet type. All packet data will be received as signed.
Host to MPS Command Packet
FUNCTION BYTES DATA TYPE DESCRIPTION
ASCII command data. Refer to the command
section of this manual for more information.
1 to 80 String
Unique to packet.
Each line/command must
be terminated with a <CR>,
<CR-LF> or <LF-CR>
MPS to Host ASCII Packet
FUNCTION BYTES DATA TYPE DESCRIPTION
ASCII data*. Refer to the Command Section of
this manual for the proper Command return
formats.
1 to 1492 String Unique to packet and varies.