Specifications

QSSC-S4R Technical Product Specification Processor Presence and Population Check
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3.
Exit firmware transfer mode (BMC reset) will cause LED to stop blinking till firmware is up and running.
4. No other sensors any fault or system status would cause any impact to Heartbeat LED.
24.22 CSS LED
QSSC-S4R has the CSS LED on back of IO Riser, which indicates Memory and Power Supply status. CSS LED
supports only two states OFF and SOLID YELLOW. On normal condition CSS LED will be OFF, CSS LED will be ON
(SOLID YELLOW) when Memory OR power supply errors are detected in the on, sleep, or standby state.
x Memory status.- Memory errors are detected by BIOS, When BIOS detects any memory errors in POST, it
notifies to BMC using “Set Fault Indication” command to light the corresponding DIMM LED, in addition to light
DIMM fault LED, BMC will also light CSS LED so that user doesn’t need to open the chassis and observe any
memory errors. The CSS LED will stay in SOLID YELLOW state until BIOS tells BMC all DIMMs OK in future
Power ON.
x Power Supply status- PS fail will happen in all power state. When the PS fail occurred, PS FW will assert the PS
Alert (SMBAlert) signal. And BMC scans PS Alert signal for any detectable errors and lights the CSS LED. Below
are the assertion conditions for the alert signal.
 IOUT over current warning
 IOUT over current fault
 POUT over power warning
 POUT over power fault
 IIN over current warning
 PIN over power warning
 VIN under voltage warning
 VIN under voltage fault
 Power good de-asserts
 Power supply failures (includes over temperature and fan failure)
24.23 Global Fan Fault LED
QSSC-S4R platform has a Fan Fault LED located on front panel next to System Status LED, which indicates Fan Fault
on system, since FAN LEDs are inside chassis, user can use this LED to find out if there are any fan failures in the
system.
On normal condition Global Fan Fault LED will be OFF. In case of fan fault (Any of system Fan), addition to relevant
FAN fault LED, Global FAN fault LED will be amber solid, Global fan fault LED will be OFF only if NONE of system fan
fault LED is ON and Global Fan Fault LED will be ON only if ANY of Fan fault LED is ON.
None of other sensors and System status contributes to Global Fan Fault LED.
In case of fan fault when system is powered off ( DC off), Global Fan fault LED will be ON so that user can see the fan
fault without opening the chassis and it will be turned off till sensor is rearmed ( int agent in case of DC on).
24.24 Power Management Bus (PMBus)
The BMC firmware implements power-management features based on the Power Management Bus (PMBus) 1.1
Specification.
24.24.1 PMBus Addressing
The power supply device address locations are shown below.
Table 182. PMBus D Device Addressing
Power Supply # PMBus Address
Power Supply 1 B0h