**** Exec. v.1.31 (m1ev131e.bin) for use with Concept 2.6.
1) Added IEC cyclical application confidence checks.

**** Exec. v.1.30 (m1ev130e.bin) for use with Concept 2.6.
Reference Resolution 192559.
1) M1E IEC Exec version 1.29 does not allow OFS to access Concept IEC unlocated variables.
2) An xxmit function block in a 171CCS78010 may fault with an error 150 under certain circumstances.

**** Exec. v.1.29 (m1ev129e.bin) for use with Concept 2.6 
1) Fixes a problem in the M1E web page where the 'TCP Retry' counter would increment every time a TCP MSTR block was activated.
2) Removes the PSH flag from the SYN and FIN packets.
3) Fixes a problem where the M1E would not respond to a second ARP request in certain conditions.
4) When 2 or more READ_REG blocks are programmed, one will periodically freeze operation anywhere from 3-5 minutes.

**** Exec. v.1.27 (m1ev127e.bin) for use with Concept 2.6 SR4
1) PSH flag is no longer set in the SYN or FIN packets.
2) The 'TCP Retry' counter in the Ethernet Statistics web page would increment each time the TCPIP MSTR block was activated. Version 1.27e prevents the counter from incrementing each time the MSTR block is activated.
3) The Ethernet port would lock up if the PLC exceeded its watchdog time (WDT) value with the 'constant sweep' function enabled.

**** Exec. v.1.26 (m1ev126e.bin) for use with Concept 2.6 SR3
1) Resolves an issue where the M1E would not respond to ICMP ping commands when communicating through routers across a WAN.

**** Exec. v.1.23 (m1ev123e.bin) for use with Concept 2.6 SR2
1) 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.
2) Closes a connection after 6 retries, even when the server ACK?s 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).
3) 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.
4) 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).
5) 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.
6) Fixes problem of communications through routers. This problem only occurred with Exec. v.1.21.
7) Now sends a RST before opening a new socket.

**** Exec. v.1.22 (m1ev122e.bin) for use with Concept 2.6 SR2
1) Resolves problem of responding to ARP request when all sockets are used.

**** Exec. v.1.21 (m1ev121e.bin) for use with Concept 2.6 SR2, SR1, and 2.5 SR2.
1) MSTR for TCP/IP configurable for sockets to remain open. This feature requires Concept 2.6 SR2. 
2) M1E PLC could crash with an error code '0835' if one segment is configured.
3) Web Page layout changed from I/O Status to I/O and Register Data Display. 
4) Fixes problem displaying web page applets only if the web pages were downloaded to the M1E using the Web Loader Utility on a Win98 Operating System.
5) Supports Classless Addressing.
6) M1E with JNN may crash with the Run LED blinking 8x immediately after a Run command is issued after loading a program. 

**** Exec. v.1.11 (m1ev111e.bin) for use with Concept 2.6 SR1.
1) When 'battery low' threshold is reached at or just below 2.7 vdc, the processor will not automatically come up 'Not Configured' on a power cycle. 

**** Exec. v.1.06 (m1ev106d.bin) for use with Concept 2.5 SR2.
1) XXMIT RS485 2-wire operation.
2) Corrects a wrong Response ID if the M1E receives a write coil request and then receives a read request before the write request has been responded to.
3) Full duplex operation resolved in RTXMIT.
4) Stopped error 200 now requires reloading of program.

**** Exec. v.1.05 (m1ei105.bin) 
Used with Concept 2.2 SR2. 
This is not a mandatory upgrade for this model M1E but it is recommended to update to the latest Exec.
1) Allows detection of an M1E problem with the I/O Bus network. Reference Resolution #924.
2) The processors Run LED would flash 4 times with a stopped error code 631 when modbus read or write coil messages were sent to it over Ethernet.
3) The M1E will now respond immediately after a retry of the request instead of waiting for a one second timeout.
4) M1E's can now handle multiple Modbus messages in a single packet from NOE211's.
5) Duplicate IP address checks were only initiated at power up. M1E's will now re-check for duplicate IP addresses when a link (connection of the cable) is made.

**** Exec. v.1.04 (m1ei104.bin)
1) Contains embedded web pages.
Release of the IEC exec. for this processor to be used with Concept 2.2 SR2.