ACC-72EX User Manual
DPRAM Memory Map
36
Communication Channel Error
This field holds the current error code of the communication channel. If the cause of error is resolved, the
communication error field is set to zero (= RCX_S_OK) again. Not all of the error codes are supported in
every implementation.
Watchdog Timeout
This field holds the configured Watchdog timeout value in milliseconds. The UMAC may set its
Watchdog trigger interval accordingly. If the UMAC fails to copy the value from the host Watchdog
location to the device Watchdog location, the protocol stack will interrupt all network connections
immediately, regardless of their current state.
Handshake Mode
The protocol stack supports different handshake mechanisms to synchronize process data exchange with
the UMAC. Depending on the configured mode, this mechanism insures data consistency over the entire
data image and helps synchronize the UMAC with the network. This register holds the configured
handshake mode.
Value
Definition / Description
$0
For compatibility reasons, this value is identical to 0x04 - Buffered Host Controlled IO
Data Transfer
$2
Buffered Device-Controlled I/O Data Transfer
$3
Uncontrolled Mode
$4
Buffered Host-Controlled IO Data Transfer
Host Watchdog
The protocol stack supervises the UMAC via the Watchdog function. If the UMAC fails to copy the value
from the device Watchdog location to the host Watchdog location, the protocol stack assumes that the
UMAC has a problem and shuts down all network connections.
Error Count (All Implementations)
This field holds the total number of errors detected since power-up or after a reset. The protocol stack
counts all sorts of errors in this field regardless if they were network-related or caused internally. The
counter is cleared after a power cycle, reset, or channel initialization.
Error Log Indicator (All Implementations)
Not supported yet; the error log indicator field holds the number of entries in the internal error log. The
field is set to zero if all entries are read from the log.
Number of Input Process Data Handshake Errors
TBD
Number of Output Process Data Handshake Errors
TBD
Number of Synchronization Handshake Errors
This counter will be incremented if the device detects a “not handled synchronization indication.” This
field is not supported yet.
Synchronization Status
This field is reserved for future use.
Slave State
The Slave State field indicates whether or not the master is in cyclic data exchange to all configured
slaves. If there is at least one slave missing or if the slave has a diagnostic request pending, the status