21 Supported PMBus Commands

Table 21-1 lists the PMBus commands. Commands 00h through CFh are defined in the PMBus specification and are considered to be core commands that are standardized for all manufacturers and products. For details on how core commands are implemented, please refer to the PMBus specification. Commands D0h through FEh are manufacturer specific and can be unique for each manufacturer and product.

The device columns indicate if a command is supported by a given device. The command is supported if a check mark (✓) appears in that column. Commands that are not supported by any device are grayed out.

Most commands support writing and reading. Exceptions are indicated in the Comments column.

The Data Format column indicates the format of the data:

Byte	8-bit binary value. See the PMBus specification for details for each command.
LINEAR16	16-bit linear format used for output voltage parameters. Described in Section 18.1.
LINEAR11	11-bit linear format used for parameters other than output voltage. Described in Section 18.2.
n/a	Command does not have a data field.
String	ASCII string. Described in Section 22.2 of the PMBus specification.
Byte Array	A block of data in binary format.

The Scope column indicates how each command is affected by the PAGE setting.

Common	This command does not depend on the PAGE setting. It is a common variable used by all pages.
PAGE	This command applies to the pages set by the most recent PAGE command. See Section 22.1 for details.

The Page column in Table 21-1 points to additional detail about the command. A number that is not in parenthesis corresponds to the page in the PMBus Power System Management Protocol Specification Part II – Command Language, Revision 1.2. The number in parenthesis is the page number in this document.

The Data Flash column indicates if the parameter is stored in the Default Store in Data Flash. If an x appears in that column, it is not stored. See Section 22.5 for more information.

Most commands are used for device configuration which is often only done once with the assistance of the TI provided configuration GUI. In normal operation, only a subset of the commands are used frequently. Those commands are highlighted in bold font.

Table 21-1 PMBus Commands

Code (hex)	Command	Transaction Type	Data Format [Units]	Scope	UCD91160	UCD91320	Data Flash	Comments
00	PAGE	R/W Byte	Byte	Common	✓	✓	X
01	OPERATION	R/W Byte	Byte	PAGE	✓	✓	X
02	ON_OFF_CONFIG	R/W Byte	Byte	PAGE	✓	✓
03	CLEAR_FAULTS	Send Byte	n/a	Common	✓	✓		Write Only
04	PHASE
05-0F	Reserved
10	WRITE_PROTECT
11	STORE_DEFAULT_ALL	Send Byte	n/a	Common	✓	✓		Write Only⁽²⁾
12	RESTORE_DEFAULT_ALL	Send Byte	n/a	Common				Write Only
13	STORE_DEFAULT_CODE
14	RESTORE_DEFAULT_CODE
15	STORE_USER_ALL
16	RESTORE_USER_ALL
17	STORE_USER_CODE
18	RESTORE_USER_CODE
19	CAPABILITY	Read Byte	Byte	Common	✓	✓		Read Only
1A	QUERY
1B-1F	Reserved
20	VOUT_MODE	R/W Byte	Byte	PAGE	✓	✓		The mode is fixed at 000 (Linear Mode), but the exponent can be modified. See Section 18.1 and Section 22.7 for details.
21	VOUT_COMMAND	R/W Word	LINEAR16 [V]	PAGE	✓	✓
22	VOUT_TRIM
23	VOUT_CAL_OFFSET
24	VOUT_MAX
25	VOUT_MARGIN_HIGH	R/W Word	LINEAR16 [V]	PAGE	✓	✓
26	VOUT_MARGIN_LOW	R/W Word	LINEAR16 [V]	PAGE	✓	✓
27	VOUT_TRANSITION_RATE
28	VOUT_DROOP
29	VOUT_SCALE_LOOP
2A	VOUT_SCALE_MONITOR	R/W Word	LINEAR11 [V/V]	PAGE	✓	✓
2B-2F	Reserved
30	COEFFICIENTS
31	POUT_MAX
32	MAX_DUTY
33	FREQUENCY_SWITCH
34	Reserved
35	VIN_ON
36	VIN_OFF
37	INTERLEAVE
38	IOUT_CAL_GAIN	R/W Word	LINEAR11 [mV/A = mΩ ]	PAGE				Current Sense Gain
39	IOUT_CAL_OFFSET	R/W Word	LINEAR11 [A]	PAGE
3A	FAN_CONFIG_1_2
3B	FAN_COMMAND_1	R/W Word	LINEAR11 [%]	Common
3C	FAN_COMMAND_2	R/W Word	LINEAR11 [%]	Common
3D	FAN_CONFIG_3_4
3E	FAN_COMMAND_3	R/W Word	LINEAR11 [%]	Common
3F	FAN_COMMAND_4	R/W Word	LINEAR11 [%]	Common
40	VOUT_OV_FAULT_LIMIT	R/W Word	LINEAR16 [V]	PAGE	✓	✓
41	VOUT_OV_FAULT_RESPONSE	R/W Byte	Byte	PAGE				See FAULT_RESPONSES command
42	VOUT_OV_WARN_LIMIT	R/W Word	LINEAR16 [V]	PAGE	✓	✓
43	VOUT_UV_WARN_LIMIT		R/W Word	LINEAR16 [V]	✓	✓	✓
44	VOUT_UV_FAULT_LIMIT		R/W Word	LINEAR16 [V]	✓	✓	✓
45	VOUT_UV_FAULT_RESPONSE	R/W Byte	Byte	PAGE				See FAULT_RESPONSES command
46	IOUT_OC_FAULT_LIMIT	R/W Word	LINEAR11 [A]	PAGE				⁽¹⁾
47	IOUT_OC_FAULT_RESPONSE	R/W Byte	Byte	PAGE				See FAULT_RESPONSES command
48	IOUT_OC_LV_FAULT_LIMIT
49	IOUT_OC_LV_FAULT_RESPONSE
4A	IOUT_OC_WARN_LIMIT	R/W Word	LINEAR11 [A]	PAGE				⁽¹⁾
4B	IOUT_UC_FAULT_LIMIT	R/W Word	LINEAR11 [A]	PAGE				⁽¹⁾
4C	IOUT_UC_FAULT_RESPONSE	R/W Byte	Byte	PAGE				See FAULT_RESPONSES command
4D	Reserved
4E	Reserved
4F	OT_FAULT_LIMIT	R/W Word	LINEAR11 [°C]	PAGE	✓	✓
50	OT_FAULT_RESPONSE	R/W Byte	Byte	PAGE				See FAULT_RESPONSES command
51	OT_WARN_LIMIT		R/W Word	LINEAR11 [°C]	✓	✓
52	UT_WARN_LIMIT						✓
53	UT_FAULT_LIMIT
54	UT_FAULT_RESPONSE
55	VIN_OV_FAULT_LIMIT
56	VIN_OV_FAULT_RESPONSE
57	VIN_OV_WARN_LIMIT
58	VIN_UV_WARN_LIMIT
59	VIN_UV_FAULT_LIMIT
5A	VIN_UV_FAULT_RESPONSE
5B	IIN_OC_FAULT_LIMIT
5C	IIN_OC_FAULT_RESPONSE
5D	IIN_OC_WARN_LIMIT
5E	POWER_GOOD_ON	R/W Word	LINEAR16 [V]	PAGE	✓	✓
5F	POWER_GOOD_OFF	R/W Word	LINEAR16 [V]	PAGE	✓	✓
60	TON_DELAY	R/W Word	LINEAR11 [ms]	PAGE	✓	✓		This does not apply to retries
61	TON_RISE
62	TON_MAX_FAULT_LIMIT	R/W Word	LINEAR11 [ms]	PAGE	✓	✓		Maximum time to reach POWER_GOOD_ON
63	TON_MAX_FAULT_RESPONSE	R/W Byte	Byte	PAGE				See FAULT_RESPONSES command
64	TOFF_DELAY	R/W Word	LINEAR11 [ms]	PAGE	✓	✓
65	TOFF_FALL
66	TOFF_MAX_WARN_LIMIT	R/W Word	LINEAR11 [ms]	PAGE	✓	✓
67	Reserved
68	POUT_OP_FAULT_LIMIT
69	POUT_OP_FAULT_RESPONSE
6A	POUT_OP_WARN_LIMIT
6B	PIN_OP_WARN_LIMIT
6C-77	Reserved
78	STATUS_BYTE	Read Byte	Byte	Common	✓	✓	X	Read Only
79	STATUS_WORD	Read Word	Word	Common	✓	✓	X	Read Only
7A	STATUS_VOUT	Read Byte	Byte	PAGE	✓	✓	X	Read Only
7B	STATUS_IOUT	Read Byte	Byte	PAGE			X	Read Only
7C	STATUS_INPUT
7D	STATUS_TEMPERATURE	Read Byte	Byte	PAGE	✓	✓	X	Read Only
7E	STATUS_CML	Read Byte	Byte	Common	✓	✓	X	Read Only
7F	STATUS_OTHER
80	STATUS_MFR_SPECIFIC							See MFR_STATUS on page 79
81	STATUS_FANS_1_2	Read Byte	Byte	Common				Read Only
82	STATUS_FANS_3_4	Read Byte	Byte	Common				Read Only
83-87	Reserved
88	READ_VIN
89	READ_IIN
8A	READ_VCAP
8B	READ_VOUT	Read Word	LINEAR16 [V]	PAGE	✓	✓	X	Read Only
8C	READ_IOUT	Read Word	LINEAR11 [A]	PAGE			X	Read Only
8D	READ_TEMPERATURE_1	Read Word	LINEAR11 [°C]	Common	✓	✓	X	Read Only
8E	READ_TEMPERATURE_2	R/W Word	LINEAR11 [°C]	PAGE			X
8F	READ_TEMPERATURE_3
90	READ_FAN_SPEED_1	Read Word	LINEAR11 [RPM]	Common				Read Only (Only valid when the fan is enabled.)
91	READ_FAN_SPEED_2	Read Word	LINEAR11 [RPM]	Common				Read Only (Only valid when the fan is enabled.)
92	READ_FAN_SPEED_3	Read Word	LINEAR11 [RPM]	Common				Read Only (Only valid when the fan is enabled.)
93	READ_FAN_SPEED_4	Read Word	LINEAR11 [RPM]	Common				Read Only (Only valid when the fan is enabled.)
94	READ_DUTY_CYCLE
95	READ_FREQUENCY
96	READ_POUT
97	READ_PIN
98	PMBUS_REVISION	Read Byte	Byte	Common	✓	✓		Read Only
99	MFR_ID	R/W Block (18 bytes)	String	Common	✓	✓
9A	MFR_MODEL	R/W Block (12 bytes)	String	Common	✓	✓
9B	MFR_REVISION	R/W Block (12 bytes)	String	Common	✓	✓
9C	MFR_LOCATION	R/W Block (12 bytes)	String	Common	✓	✓
9D	MFR_DATE	R/W Block (6 bytes)	String	Common	✓	✓
9E	MFR_SERIAL	R/W Block (12 bytes)	String	Common	✓	✓
9F	Reserved
A0	MFR_VIN_MIN
A1	MFR_VIN_MAX
A2	MFR_IIN_MAX
A3	MFR_PIN_MAX
A4	MFR_VOUT_MIN
A5	MFR_VOUT_MAX
A6	MFR_IOUT_MAX
A7	MFR_POUT_MAX
A8	MFR_TAMBIENT_MAX
A9	MFR_TAMBIENT_MIN
AA-AC	Reserved
AD	IC_DEVICE_ID	Block Read	String	Common	✓	✓		PMBus 1.2
AE	IC_DEVICE_REV	Block Read	String	Common	✓	✓		PMBus 1.2
AF	Reserved
B0-B4	MFR_STATUS_0-MFR_STATUS_4	Read Byte	Byte	Common	✓	✓		Command Byte values are to be used with SMBALERT_MASK (0x1B) to write/read MFR_STATUS SMB Alert mask
B5	FIRST_BLACK_BOX_FAULT_INFO(USER_DATA_05)	Block Write/Read (16 Bytes)	Byte Array	Common	✓	✓
B6	LAST_BLACK_BOX_FAULT_INFO(USER_DATA_06)	Block Read	Byte Array	Common	✓	✓
B7	Reserved	Block Read	Byte Array	Common
B8	RAIL_PROFILE(USER_DATA_08)	Block Read	Byte Array	PAGE	✓	✓
B9	RAIL_STATE(USER_DATA_09)	R Block	Byte Array	PAGE	✓	✓		Provides the current, previous, and pending rail states.
BA-BF	USER_DATA_10 - USER_DATA_15
C0-CF	Reserved
D0	FAULT_PIN_CONFIG (MFR_SPECIFIC_00)	R/W Block	Byte Array	Common	✓	✓		Must be configured along with GPI_CONFIG which selects the external pin to use for the input source
D1	VOUT_CAL_MONITOR (MFR_SPECIFIC_01)	R/W Word	LINEAR16 [V]	PAGE	✓	✓	X	Offset calibration value for the sensor used in READ_VOUT. Signed.
D2	SYSTEM_RESET_CONFIG (MFR_SPECIFIC_02)	R/W Block (4, 6, or 9 bytes)	Byte Array	Common	✓	✓	X	Configures the System Reset function
D3	SYSTEM_WATCHDOG_CONFIG (MFR_SPECIFIC_03)	R/W Block (6 bytes)	Byte Array	Common	✓	✓		Configures the System Watchdog function
D4	SYSTEM_WATCHDOG_RESET (MFR_SPECIFIC_04)	Send Byte	n/a	Common	✓	✓		Resets the System Watchdog timeout counter
D5	MONITOR_CONFIG (MFR_SPECIFIC_05)	R/W Block	Byte Array	Common	✓	✓		Configure pins for monitoring (voltage, temperature, and so forth)
D6	NUM_PAGES (MFR_SPECIFIC_06)	Read Byte	Byte	Common	✓	✓		Read Only Returns the number of active pages
D7	RUN_TIME_CLOCK (MFR_SPECIFIC_07)	R/W Block	Byte Array	Common	✓	✓		Time provided in RTC format (Year, Month, Day, Hour, Minute, Second, Milisecond).
D8	RUN_TIME_CLOCK_TRIM (MFR_SPECIFIC_08)	R/W Word	Byte Array (LINEAR11)	Common	✓	✓		PPM adjustment for calibrating the run-time clock
D9	Reserved (MFR_SPECIFIC_09)		n/a
DA	USER_RAM_00 (MFR_SPECIFIC_10)	R/W Byte	Byte	Common	✓	✓		RAM value that is set to 0 during device reset. By writing a nonzero value to this variable and then monitoring its value, a host can determine that a device reset has occurred.
DB	SOFT_RESET (MFR_SPECIFIC_11)	Send Byte	n/a	Common	✓	✓		Write Only This command restarts the controller firmware
DC	RESET_COUNT (MFR_SPECIFIC_12)	R/W Word (1)	2 Bytes (1)	Common				The number of times that the device has been reset.
DD	PIN_SELECTED_RAIL_STATES (MFR_SPECIFIC_13)	Read Block (18 bytes)	Byte Array	Common	✓	✓		Allows encoding on input pins to decide the state of each of the rails.
DE	RESEQUENCE (MFR_SPECIFIC_14)	Write Word	2 Bytes	Common	✓	✓	X	Commands selected rails to resequence. (Write Only)
DF	CONSTANTS (MFR_SPECIFIC_15)	Read Block (8 bytes)	Byte Array	Common	✓	✓		Fixed information about the device
E0	PWM_SELECT (MFR_SPECIFIC_16)	R/W Byte	Byte	Common	✓	✓	X	Determines which PWM the PWM_CONFIG command applies to
E1	PWM_CONFIG (MFR_SPECIFIC_17)	R/W Block (8 bytes)	Byte Array	Common	✓	✓		Configures a PWM (frequency, duty cycle, and phase)
E2	PARM_INFO (MFR_SPECIFIC_18)	R/W Block (5 bytes)	Byte Array	Common	✓	✓	X	Parm Info: <parm base> <parm offset low byte> <parm offset high byte> <parm count> <parm size> This command sets the parameters used by the Parm Value command
E3	PARM_VALUE (MFR_SPECIFIC_19)	R/W Block	Byte Array	Common	✓	✓	X	Value transferred to memory location chosen by the PARM_INFO command
E4	TEMPERATURE_CAL_GAIN (MFR_SPECIFIC_20)	R/W Word	LINEAR11 [°C/V]	PAGE	✓	✓		Gain calibration for the external sensors used by the READ_TEMPERATURE_2 command
E5	TEMPERATURE_CAL_OFFSET (MFR_SPECIFIC_21)	R/W Word	LINEAR11[°C]	PAGE	✓	✓		Offset calibration for the external sensors used by the READ_TEMPERATURE_2 command
E6	SET_BREAKPOINTS (MFR_SPECIFIC_22)	R/W Word	2 Bytes	Page	✓	✓		Used to set breakpoints for given states
E7	DEBUG_CONTINUE (MFR_SPECIFIC_23)	R/W Byte (4 Bytes)	Byte Array	Common	✓	✓		Used to indicate a page should exit the breakpoint state
E8	(MFR_SPECIFIC_24)
E9	FAULT_RESPONSES (MFR_SPECIFIC_25)	R/W Block (9 Bytes)	Byte Array	PAGE	✓	✓		Defines the response to all supported faults
EA	LOGGED_FAULTS (MFR_SPECIFIC_26)	R/W Block	Byte Array	Common	✓	✓		Flags in Data Flash that are set when each fault type occurs on each page ⁽²⁾
EB	LOGGED_FAULT_DETAIL_INDEX (MFR_SPECIFIC_27)	R/W Word	2 bytes	Common	✓	✓	X	Number of LOGGED_FAULT_DETAIL entries and a read/write index into those entries
EC	LOGGED_FAULT_DETAIL (MFR_SPECIFIC_28)	Read Block	Byte Array	Common	✓	✓		Detail information about the faults that have occurred
ED	LOGGED_PAGE_PEAKS (MFR_SPECIFIC_29)	R/W Block	Byte Array, Byte [°C], LINEAR16 [V], LINEAR11 [amp]	PAGE				Peak temperature, voltage, and current for a given page, stored in Data Flash ⁽²⁾
EE	LOGGED_COMMON_PEAKS (MFR_SPECIFIC_30)	R/W Byte	Byte [°C]	Common				Peak internal temperature ⁽²⁾
EF	LOGGED_FAULT_DETAIL_ENABLES (MFR_SPECIFIC_31)	R/W Block	Byte Array	Common	✓	✓		Selectable fault logging by rail and by fault type
F0	EXECUTE_FLASH (MFR_SPECIFIC_32)	Send Byte	n/a	Common				If in ROM mode, starts the device executing in FLASH mode. If already in FLASH mode, command has no effect.
F1	SECURITY (MFR_SPECIFIC_33)	R/W Block (6 bytes)	Binary Array	Common				Sets the password used to secure the unit against unauthorized modification of its settings
F2	SECURITY_BIT_MASK (MFR_SPECIFIC_34)	R/W Block (32 bytes)	Binary Array	Common				Configures which commands are password protected.
F3	MFR_STATUS (MFR_SPECIFIC_35)	Read Block (2 or 4 bytes)	Byte Array	PAGE	✓	✓	X	Replaces the STATUS_MFR_SPECIFIC command
F4	GPI_FAULT_RESPONSES (MFR_SPECIFIC_36)	R/W Block	Byte Array	PAGE	✓	✓		GPI Fault Responses per page
F5	MARGIN_CONFIG (MFR_SPECIFIC_37)	R/W Byte	Byte	PAGE	✓	✓		Selects the margining pin and other margining configuration
F6	SEQ_CONFIG (MFR_SPECIFIC_38)	R/W Block (6-12 bytes)	Byte Array	PAGE	✓	✓		Configures sequencing dependencies and enable pin
F7	GPO_CONFIG_INDEX (MFR_SPECIFIC_39)	R/W Byte	Byte	Common	✓	✓	X	Selects to which GPO the GPO_CONFIG command applies
F8	GPO_CONFIG (MFR_SPECIFIC_40)	R/W Block (20 or 29 bytes)	Byte Array	Common	✓	✓		Configures output pins and their dependencies
F9	GPI_CONFIG (MFR_SPECIFIC_41)	R/W Block (13 bytes)	Byte Array	Common	✓	✓		Configures input pins
FA	GPIO_SELECT (MFR_SPECIFIC_42)	R/W Byte	Byte	Common	✓	✓	X	Determines to which GPIO the GPIO_CONFIG command applies
FB	GPIO_CONFIG (MFR_SPECIFIC_43)	R/W Byte	Byte	Common	✓	✓		Set or get the state of a GPIO
FC	MISC_CONFIG (MFR_SPECIFIC_44)	R/W Block	2 Bytes	Common	✓	✓		Miscellaneous configuration settings
FD	DEVICE_ID (MFR_SPECIFIC_45)	Read Block (up to 32 bytes)	String	Common	✓	✓		Returns ASCII string with hardware and firmware version information of the controller
FE	Mfr_Specific_Extended_Command				✓	✓
FF	PMBUS_Extended_Command				✓	✓

(1) These values are only applied when associated voltage is in regulation. If there is not an associated voltage monitor, these values are applied after the rail is enabled and after TON_DELAY.

(2) There is a chance that a write to this command receives a NACK. When the firmware starts a periodic or commanded update of data flash, it can take up to 100 ms to complete. During that time, writes to these commands receive a NACK. If this occurs, wait 100 ms and retry the command. This note only applies if the brownout feature is not enabled (see brownout enable mode in MISC_CONFIG).