Rainbow Electronics MAX34441 - Manual (Page 29)

PMBus 5-Channel Power-Supply Manager
and Intelligent Fan Controller
MAX34441
29
STORE_DEFAULT_ALL (11h)
The STORE_DEFAULT_ALL command instructs the device to transfer the device configuration information to the
internal flash memory array. Not all information is stored. Only configuration data is stored, not any status, or opera-
tional data. If an error occurs during the transfer, ALERT asserts if enabled and the CML bit in STATUS_BYTE and
STATUS_WORD is set to 1. No bits are set in STATUS_CML. It is NOT recommended to use the STORE_DEFAULT_ALL
command while the device is operating power supplies or fans. The device is unresponsive to PMBus commands
and does not monitor power supplies while transferring the configuration. This command is write-only. There is no data
byte for this command.
USER NOTE: V
DD must be above 2.9V for the device to perform the STORE_DEFAULT_ALL command.
RESTORE_DEFAULT_ALL (12h)
The RESTORE_DEFAULT_ALL command transfers the default configuration information from the internal flash memory
array to the user memory registers in the device. The RESTORE_DEFAULT_ALL command should only be executed
when the device is not operating the power supplies or fans. Upon a device reset, this command is automatically
executed by the device without PMBus action required. This command is write-only. There is no data byte for this
command.
CAPABILITY (19h)
The CAPABILITY command is used to determine some key capabilities of the device. The CAPABILITY command is
read-only. The message content is described in Table 13.
VOUT_MODE (20h)
The VOUT_MODE command is used to report the data format of the device. The device uses the DIRECT format for all
the voltage-related commands. The value returned is 40h, indicating DIRECT data format. This command is read-only.
If a host attempts to write this command, the CML status bit is asserted. See Table 3 for the m, b, and R values for the
various commands.
VOUT_MARGIN_HIGH (25h)
The VOUT_MARGIN_HIGH command loads the device with the voltage to which the power-supply output is to be
changed when the OPERATION command is set to margin high. If the power supply is already operating at margin
high, changing VOUT_MARGIN_HIGH has no effect on the output voltage. The device only adjusts the power supply to
the new VOUT_MARGIN_HIGH voltage after receiving a new margin high OPERATION command. The 2 data bytes are
in DIRECT format. If the device cannot successfully close-loop margin the power supply, the device keeps attempting
to margin the supply and does the following:
1) Sets the NONE OF THE ABOVE bit in STATUS_BYTE.
2) Sets the NONE OF THE ABOVE and MFR bits in STATUS_WORD.
3) Sets the MARGIN_FAULT bit in STATUS_MFR_SPECIFIC.
4) Notifies the host through ALERT assertion (if enabled in MFR_MODE).
Table 13. CAPABILITY Command Byte
BIT DESCRIPTION MEANING
7 Packet-Error Checking 0 = PEC not supported.
6:5 PMBus Speed 00 = Maximum supported bus speed is 100kHz.
4 ALERT
1 = Device supports an ALERT output (if ALERT is enabled in MFR_MODE).
0 = Device does not support ALERT output (ALERT is disabled in MFR_MODE).
3:0 Reserved Always returns 0000.