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171CCC9x0x0 M1E Processor 984LL Exec. Upgrade to v.1.23

Release Notice

The purpose of this resolution is to inform Momentum M1E users that the 984LL Exec. has been upgraded to version 1.23.

Goals and Symptoms

Resolves an issue with reconnecting from an M1E client to a server using I/O scanner if the M1E is power cycled. The M1E will now reconnect with a different port number. Resolves a reconnect issue when the gateway is powered down.

  1. Closes a connection after 6 retries, even when the server ACKs the M1E. (based on single application where the Linux stack came up before the application. It established a connection but did not respond since the application was not yet functional).
  2. Maximum time between 2 retries on a network that has not yet established communications (that it has not received a response to its queries) is 1 second.
  3. State machine changed to send an ACK in response to SYN,ACK and not send it with the query. (due to interoperability issues with OTB).
  4. Any log-in to the controller can be monitored by viewing bit 3 in the first 40xxx Status Block Register.
    1 = someone logged in on any one of the Modbus ports
    0 = no one logged in
    This function accurate as long as the PLC is in RUN mode.
  5. Fixes problem of communications through routers. This problem only occurred with Exec. v.1.21.
  6. Now sends a RST before opening a new socket.

Facts and Changes

This resolution affects 171CCC98020, 171CCC96020, 171CCC98030, and 171CCC96030 processors using the 984LL Exec.

  • Note: It is recommended to power cycle the M1E immediately after downloading an Exec.

Causes and Fixes

Installing 984LL Exec. v.1.23 resolves the above mentioned issues

Legacy KB System (APS) Data: RESL170037 V1.0, Originally authored by on , Last Edited by on
Related ranges: Modicon Momentum
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