PMBus Power System Mgt Protocol Specification – Part II – Revision 1.2
© 2010 System Management Interface Forum, Inc. Page 4 of 106
All Rights Reserved
9.3. Making And Calibrating Output Current Measurements ............................................................... 30
9.4. Deleted ......................................................................................................................................... 31
10. Fault Management And Reporting ................................................................................................... 31
10.1. Monitoring Operation ................................................................................................................ 31
10.2. General Description Of PMBus Device Fault Management ..................................................... 33
10.2.1. Warning Conditions ........................................................................................................... 33
10.2.2. Fault Conditions ................................................................................................................. 33
10.2.3. Clearing Warning Or Fault Bits .......................................................................................... 33
10.2.4. Clearing Individual Bits ...................................................................................................... 34
10.2.5. Clearing Bits In The STATUS_BYTE And STATUS_WORD ............................................ 34
10.2.5.1. General Rules ................................................................................................................ 34
10.2.5.2. Special Case: NONE OF THE ABOVE .......................................................................... 35
10.2.5.3. Exceptions ...................................................................................................................... 35
10.2.6. Immediate Reassertion After Clearing If Condition Is Still Present ................................... 35
10.3. Conceptual View Of How Status Bits And SMBALERT# Work ................................................ 35
10.4. Setting Fault And Warning Thresholds ..................................................................................... 36
10.5. Setting The Response To A Detected Fault Condition ............................................................. 36
10.5.1. Response To Voltage, Temperature And TON_MAX Faults ............................................. 37
10.5.2. Response To Current Faults .............................................................................................. 38
10.6. Reporting Faults And Warnings To The Host ........................................................................... 40
10.6.1. SMBALERT# Signal And Process ..................................................................................... 40
10.6.2. Direct PMBus Device To Host Communication ................................................................. 41
10.7. Clearing A Shutdown Due To A Fault ....................................................................................... 41
10.8. Data Transmission Faults ......................................................................................................... 41
10.8.1. Corrupted Data .................................................................................................................. 42
10.8.2. Sending Too Few Bits ........................................................................................................ 42
10.8.3. Reading Too Few Bits ....................................................................................................... 42
10.8.4. Host Sends Or Reads Too Few Bytes ............................................................................... 42
10.8.5. Host Sends Too Many Bytes ............................................................................................. 43
10.8.6. Reading Too Many Bytes .................................................................................................. 43
10.8.7. Device Busy ....................................................................................................................... 43
10.9. Data Content Faults .................................................................................................................. 44
10.9.1. Improperly Set Read Bit In The Address Byte ................................................................... 44
10.9.2. Unsupported Command Code ........................................................................................... 44
10.9.3. Invalid Or Unsupported Data ............................................................................................. 44
10.9.4. Data Out Of Range Fault ................................................................................................... 45
10.9.5. Reserved Bits..................................................................................................................... 45
11. Address, Memory, Communication And Capability Related Commands ......................................... 46
11.1. WRITE_PROTECT ................................................................................................................... 46
11.2. STORE_DEFAULT_ALL ........................................................................................................... 46
11.3. RESTORE_DEFAULT_ALL ...................................................................................................... 46
11.4. STORE_DEFAULT_CODE ....................................................................................................... 47
11.5. RESTORE_DEFAULT_CODE .................................................................................................. 47
11.6. STORE_USER_ALL ................................................................................................................. 47
11.7. RESTORE_USER_ALL ............................................................................................................ 48
11.8. STORE_USER_CODE ............................................................................................................. 48
11.9. RESTORE_USER_CODE ........................................................................................................ 48
11.10. PAGE ........................................................................................................................................ 49
11.11. PHASE ...................................................................................................................................... 50
11.12. CAPABILITY ............................................................................................................................. 51
11.13. QUERY ..................................................................................................................................... 51
11.14. PAGE_PLUS_WRITE ............................................................................................................... 52
11.15. PAGE_PLUS_REA D ................................................................................................................. 53
12. On, Off And Margin Testing Related Commands ............................................................................ 53
12.1. OPERATION ............................................................................................................................. 53
12.2. ON_OFF_CONFIG.................................................................................................................... 54