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6F8C0903
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4.2 S Controller Interface Buffer Memory Configuration
4
(2) Down Information (05D4H: 1 word)
This register stores data of the cause of the DN311 getting into down mode. When
this happens, the 7-segment LED on the front panel show the following down codes.
(3) Polling/bit strobe scan cycle (05CFH to 05D3H: 5 words)
This area stores the DN311's scan time in milliseconds during transmission in polling
mode or bit strobe mode.
Asynchronous mode: The scan cycle means the time from when the DN311 finishes
data input/output with all slave devices until it restarts data input/output next.
• If all the slave devices are in polling mode, the scan cycle means the time
from the start of a polling input/output until the restart of another polling input/
output next.
• If all the slave devices are in bit strobe mode, the scan cycle means the time
from the start of a bit strobe input/output until the restart of another bit strobe
input/output next.
• If slave devices of polling mode and bit strobe mode are mixedly used, the
scan cycle means the time from the finish of a polling input/output following
the start of a bit strobe input/output until the restart of another bit strobe input/
output next.
Synchronous mode: The scan completion time means the time from when "1" is
written in the bit strobe output data semaphore/polling output data semaphore
until the DN311 writes "1" in the input data semaphore.
Table 4-4 Down Information
Down Code
(hexadecimal)
Cause of Down Mode
F0H
Watchdog timeout
F1H
Memory bus error
F2H
TRAP
F3H
ROM's BCC check error (at DN311 start)
F4H
RAM's read/write error (at DN311 start)
F5H
Read/Write error pndtw3 for S controller communication (at DN311 start)
F6H
DN311 node address setting error
F7H
DN311 network communication rate setting error
F8H
Configuration data EEPROM read error
Table 4-5 Scan Cycles
05CFH
Scan cycle/scan completion time
05D0H
Asynchronous mode: Minimum scan cycle
05D1H
Asynchronous mode: Maximum scan cycle
05D2H
Synchronous mode: Minimum scan completion time
05D3H
Synchronous mode: Maximum scan completion time