Model MMU-1600G Series Op Man - Ver 1.07.23 - Rev 20151026DL
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2.7.7 Logging Options
2.7.7.1 Log Field Changes
When this feature is enabled the monitor will make entries in the Signal Sequence log only when an input has changed state.
All inputs (AC and DC) are checked every 33 milliseconds for a change in state. If any input changed state, a new entry is
placed in the Signal Sequence log. If this feature is disabled the monitor will make a new entry in the Signal Sequence log
every 33 milliseconds. The disabled mode is typically the most useful mode for this feature but the Signal Sequence log can
only record two seconds prior to the fault is this mode. However, when troubleshooting Short Yellow or Short Clearance
faults, it may be desirable to record a longer Signal Sequence log. With this feature enabled the Signal Sequence log will
typically record 40 to 50 seconds prior to the fault. The factory default for this feature is disabled.
2.7.7.2 Log Local Flash Events
When this feature is enabled the monitor will record Local Flash events in the Prior Faults log. Disabling this feature is
useful when an intersection is normally put into Local Flash (time of day, etc) and you do not want to fill up the Prior Faults
log with non-fault events. The factory default for this feature is
YES
.
2.7.7.3 Log CVM Events
When this feature is enabled the monitor will record CVM events in the Prior Faults log. Disabling this feature is useful
when an intersection is normally put into flash using CVM (time of day, etc) and you do not want to fill up the Prior Faults
log with non-fault events. The factory default for this feature is
YES
.
2.8
DIAGNOSTICS
The monitor is provided with a series of resident self-check diagnostics capabilities. Diagnostic failures are latched in the
fault condition until the unit is reset by the activation of the front panel reset pushbutton or activation of the reset input. A
diagnostic failure is not reset by a monitor Power Failure.
Failure of any of these diagnostics will result in the monitor Diagnostic Failure bit (bit 73) of the Type 129 Frame being set
to 1. NOTE: Port 1 communications may not be possible during certain diagnostic failures.
2.8.1 Memory
The monitor verifies all memory elements on power up or upon reset of a Diagnostics failure. A failure of any of the
memory tests will generate a diagnostics failure.
RAM Diagnostics: Test patterns are written to every byte of RAM in the monitor. After each write a read is performed
to verify that the pattern is correct.
Flash ROM Diagnostics: A checksum is calculated for all of the ROM in the monitor. The calculated value is compared
to a preprogrammed value stored in the ROM.
EEPROM Diagnostics: A checksum is calculated for all of the internal EEPROM in the monitor. The calculated value is
compared to a preprogrammed value stored in the internal EEPROM.
Programming Card EEPROM Diagnostics: A checksum is calculated for all of the EEPROM on the programming card.
The calculated value is compared to a preprogrammed value stored in the programming card EEPROM.
The monitor continues to verify the RAM, Program Flash, Storage Flash, and Programming Card EEPROM during normal
operation. Checksums are calculated for the Program Flash and Storage Flash at a rate of at least 1024 bytes per second.
Checksums are calculated for the entire Programming Card EEPROM once per second.
2.8.2 Microprocessor Monitor
The monitor continuously checks the operation of its microprocessor. The monitoring circuit receives a signal or logic state
transition at least once every 33 milliseconds from the microprocessor. When the signal or logic state transition is not
received for more than 50 milliseconds a diagnostics fault is generated.
2.8.3 Internal Voltage Monitors
The monitor checks the voltage levels of the internal DC power supplies. The +12 volt, +5 volt, d3.3 volt, analog
+3.3 volt, and analog -3.3 volt power supplies are all monitored for proper voltage levels. When any of these voltage levels
is invalid for more than 125 milliseconds a diagnostics fault is generated. These faults will not be logged by the monitor, as
any one of these voltages being invalid will immediately place the monitor in a diagnostic failure mode with the
microprocessor held in reset. This prevents any false faults or missed faults due to an internal power supply malfunction.
