LabJack UE9 - Page 67

The watchdog settings (bytes 7-10) are stored in non-volatile flash memory, so every call to this function where settings are
changed causes a flash erase/write. The Control flash has a rated endurance of at least 20000 writes, which is plenty for
reasonable operation, but if this function is called in a high-speed loop the flash could be damaged.
Note: Do not call this function while streaming.
Command:
Byte
0
Checksum8
1
0xF8
2
0x05
3
0x09
4
Checksum16 (LSB)
5
Checksum16 (MSB)
6
0x00
7
WatchdogOptions
Bit 7: Reserved (0)
Bit 6: Reset Comm on Timeout
Bit 5: Reset Control on Timeout
Bit 4: Update Digital I/O B on Timeout
Bit 3: Update Digital I/O A on Timeout
Bit 1: Update DAC1 on Timeout
Bit 0: Update DAC0 on Timeout
8-9
TimeoutPeriod
10
DIOConfigA
Bit 7: State
Bit 4-0: Digital IO #
11
DIOConfigB
Bit 7: State
Bit 4-0: Digital IO #
12
DAC0 (LSB)
13
DAC0
Bit 7: Enabled
Bits 3-0: Upper 4 bits of output
14
DAC1 (LSB)
15
DAC1
Bit 7: Enabled
Bits 3-0: Upper 4 bit of output
Response:
Byte
0
Checksum8
1
0xF8
2
0x01
3
0x09
4
Checksum16 (LSB)
5
Checksum16 (MSB)
6
Errorcode
7
WatchdogOptions
WatchdogOptions: The watchdog is enabled when this byte is nonzero. Set the appropriate bit to reset either or both
processors, update the state of 1 or 2 digital I/O, or update 1 or both DACs.
TimeoutPeriod: The watchdog timer is reset to zero on any incoming Control communication. Note that most functions
consist of a write and read, but StreamData is outgoing only and does not reset the watchdog. If the watchdog timer is not
reset before it counts up to TimeoutPeriod, the actions specified by WatchdogOptions will occur. The watchdog timer has a
clock rate of about 1 Hz, so a TimeoutPeriod range of 1-65535 corresponds to about 1 to 65535 seconds.
DIOConfig#: Determines which digital I/O is affected by the watchdog, and the state it is set to. The digital I/O # is a value
from 0-22 according to the following: 0-7 => FIO0-FIO7, 8-15 => EIO0-EIO7, 16-19 => CIO0-CIO3, 20-22 => MIO0-MIO2
DAC#: Specifies values for the DACs on watchdog timeout. The UE9 has 12-bit analog outputs, so pass an output value
between 0 and 4095, plus set bit 7 of the high byte accordingly. If Bit7 is set on either DAC, then both are enabled. To
disable the DACs (set to high-impedance), bit 7 must be 0 for both DACs.
5.3.13.2 - WatchdogRead
Reads the current watchdog settings.
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