PMBus Transfer Commands

Table 1. PMBus Transfer Commands
Code	Command	Description	Transaction Type	Local Register Name	Data Bytes (Format)	Scope
00h	PAGE	Selects the supply for the single supply commands (Scope = PAGE). The PAGE number defined corresponds to the SUPPLY number defined by the user design.	Read Write	PMBUS_PAGE	1	COMMON
03h	CLEAR_FAULTS	Clears all fault bits in all status registers simultaneously. At the same time, the device negates (clears, releases) its SMBALERT# signal output if the device is asserting the SMBALERT.	Write	Clears PMBUS_STATUS_* (all)	0	COMMON
19h	CAPABILITY	Allows host to identify key capabilities of PMBus device, i.e., PEC support, max bus speed, SMBALERT support. Returns `0x30`.	Read	Read-only value: 0x30	1	COMMON
20h	VOUT_MODE	To set and query the data format used by device for output voltage related data.	Read Write	Read-only value: 0x12	1	COMMON
40h	VOUT_OV_FAULT_LIMIT	Sets the over-voltage value that causes an output over-voltage fault. Limit shared with SUPPLYn_TH_UPPER register, where n is the PMBUS PAGE.	Read Write	DEVICE_TEMP_TH_UPPER.	2 (LINEAR16)	COMMON
44h	VOUT_UV_FAULT_LIMIT	Sets the under-voltage value that causes an output over-voltage fault. Limit shared with SUPPLYn_TH_LOWER register, where n is the PMBUS PAGE.	Read Write	DEVICE_TEMP_TH_LOWER	2 (LINEAR16)	COMMON
4Fh	OT_FAULT_LIMIT	Command sets the temperature of the unit at which it should indicate an over temperature fault OT. Accesses to the OT_TEMP_TH_UPPER register.	Read Write	OT_TEMP_TH_UPPER	2 (LINEAR11)	COMMON
51h	OT_WARNING_LIMIT	Command sets the temperature of the unit at which it should indicate an over temperature warning ALM_OV[0]. Accesses to the DEVICE_TEMP_TH_UPPER register.	Read Write	DEVICE_TEMP_TH_UPPER	2 (LINEAR11)	COMMON
52h	UT_WARNING_LIMIT	Command sets the temperature of the unit at which it should indicate an under temperature warning ALM_UV[0]. Accesses to the DEVICE_TEMP_TH_LOWER register.	Read Write	OT_TEMP_TH_LOWER	2 (LINEAR11)	COMMON
53h	UT_FAULT_LIMIT	Command sets the temperature of the unit at which it should indicate an under temperature fault UT. Accesses to the OT_TEMP_TH_LOWER register.	Read Write	OT_TEMP_TH_LOWER	2 (LINEAR11)	COMMON
78h	STATUS_BYTE	Command returns one byte of information with a summary of the most critical faults.	Read	PMBUS_STATUS_BYTE	1	COMMON
79h	STATUS_WORD	Command returns two bytes of information with a summary of the unit's fault condition.	Read	PMBUS_STATUS_WORD	2	COMMON
7Ah	STATUS_VOUT	Command returns one byte representing VOUT status.	Read Write	PMBUS_STATUS_VOUT<page>	1	PAGE
7Dh	STATUS_TEMPERATURE	Command returns temperature status.	Read Write	PMBUS_STATUS_TEMPERATUR	1	COMMON
7Eh	STATUS_CML	Command returns communication, logic, and memory status.	Read Write	PMBUS_STATUS_CML	1	COMMON
8Bh	READ_VOUT	Command returns the actual, measured (not commanded) output voltage in the LINEAR16 format.	Read	SUPPLYn	2 (LINEAR16)	PAGE
8Dh	READ_TEMPERATURE_1	Command returns temperature readings.	Read	DEVICE_TEMP	2 (LINEAR11)	COMMON
98h	PMBUS_REVISION	PMBUS_REVISION command stores or reads the revision of the PMBus to which the device is compliant.	Read	Read-only value: 0x42	1	COMMON
99h	MFR_ID	PMBUS_REVISION command reads the AMD manufacturer's ID. The AMD manufacturer ID corresponds to [11:0] of the of the IDCODE_REGISTER. For example, 000010010011 read as three bytes:0x000093.	Read		3	COMMON
9Ah	MFR_MODEL	The command is used to read the manufacturer's model number of the part. It corresponds to bits [27:12] of the IDCODE_REGISTER in the device specific BSDL for specific model ID.	Read		3	COMMON
9Bh	MFR_REVISION	The command is used to either set or read the manufacturer's revision number. See IDCODE_REGISTER in the device specific BSDL for specific Revision ID.	Read		2	COMMON
D0h	MFR_SPECIFIC_00	(MFR_SELECT_REG) A manufacturer-specific command to program config and sequence registers. The command is used to select memory-mapped registers.	Read Write		2	COMMON
D1h	MFR_SPECIFIC_01	(MFR_ACCESS_REG) Read or write data on the selected register. To write to a register with this command the register space must be unlocked. The PCSR_LOCK register can be accessed via PMBUS.	Read Write		4	COMMON
D2h	MFR_SPECIFIC_02	(MFR_READ_VOUT_MAX) A manufacturer-specific command. Reads maximum recorded value for the selected supply.	Read	SUPPLYn_MAX	2 (SLINEAR16)	PAGE
D3h	MFR_SPECIFIC_03	(MFR_READ_VOUT_MIN) A manufacturer-specific command. Reads minimum recorded value for the selected supply.	Read	SUPPLYn_MIN	2 (SLINEAR16)	PAGE