UM0718
Advanced PMBus GUI description
Doc ID 15846 Rev 1
19/31
the transmitter is different to that of the receiver. In this case, the GUI displays the error
message ‘PEC failure’. In the case of the receiver, the PEC value is received after the last
byte by this board and compared with a calculated PEC value. The GUI displays the error
message ‘PEC failure’, if the PEC value of the transmitter is different to the calculated value.
The speed of the PMBus communication can be configured by checking the corresponding
box against 100 kHz or 400 kHz.
3.1.2 Memory
selection
This section has two buttons to move the PMBus related data from operating memory to
non-volatile memory or vice-versa. At the conceptual level, the PMBus slave operates from
the values stored in the volatile memory while a non-volatile memory (if supported by the
PMBus slave) is called default store. The restore button instructs the PMBus slave device to
copy the entire contents of the non-volatile user store memory to the matching locations in
the operating memory. The values of the operating memory are overwritten by the values
read from the non-volatile memory. Any item in the user store, not having a matching
location in the operating memory, is simply ignored.
Note:
The user must confirm the behavior of store and restore commands with the manufacturer.
Sometimes, use of the above commands while the device is operating, may lead to
undesirable or damaging behavior.
Figure 18.
Memory section
3.1.3
Device control section
This section can be subdivided into four blocks:
1.
Operation
2. Control
signal
3. ON/OFF
configuration
4. Status
As soon as the PMBus slave is selected, all the parameters are read automatically from the
device. They can then be modified by the user. In the control signal section, the checked box
indicates the signal value to turn ON the selected slave. This may be low (if the slave is
active low enabled) or high (if the slave is active high enabled). The user can switch off the
device by reversing this signal. It must be switched on with the correct control signal value
(high or low) to restart the operation.
Figure 19.
Control signal section
The status section indicates the PMBus status of the selected slave and can be periodically
monitored by putting the update interval value. When the clear faults button is pressed, all
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