Intel® RAID Adapters RS3P4TF160F and RS3P4MF088F Hardware User Guide
17
3.12
Over Temperature Protection
The tri-mode Intel RAID adapters are designed to operate at a maximum internal chassis temperature of
55 °C, with a minimum of 200 LFM airflow. This ensures that the internal ROC IC operates at less than 105 °C.
If for any reason there’s an overheating, the internal ROC overtemperature protection circuitry operate
s as
described next:
•
If the ROC reaches 110 °C, the overtemperature LED is turned on, I/O is throttled and the event
“MR_EVT_CTRL_TEMP_ABOVE_OPTIMAL_RANGE” is registered in the adapter’s log.
•
If the ROC temperature goes down below 105 °C (mostly due to I/O throttling), the over temperature LED
is turned off. T
he event “MR_EVT_CTRL_TEMP_WITHIN_OPTIMAL_RANGE” is registered
in the adapter’s
log and I/O throttling is turned off.
•
If the ROC reaches 116 °C, the overtemperature LED continues to light, I/O continues to throttle, the
event “MR_EVT_CTRL_TEMP_CRITICAL”
is registered in the adapter’s log
. Then, after 10 seconds of
operation, the cache is flushed, pending I/Os are completed and the ROC enters
the “Montask” state, in
which state all I/Os stop except through the UART debugging interface.
3.13
UART Interface
The tri-mode Intel RAID adapters include a UART interface for special debugging purposes. The UART
connector debug port requires a special cable and Intel support to gather detailed ROC / IOC status. The
UART connector uses the layout shown in the following table.
Table 6. UART Connector Pinout
Pin
Function
1
1
UART_TX
2
Gnd
3
UART_RX
4
1.8 V
Note 1:
Pin 1 has a square solder mask, while the other pins have a round solder mask.
The default communication parameters are 921,600 b/s, 8-bit characters, no parity bit, one stop bit, and no
XON / XOFF flow control.
3.14
Optional Intel® RAID Maintenance Free Backup Unit (RMFBU)
To protect the integrity of cached data on the Intel RAID adapter during a power loss event, the tri-mode
Intel RAID Adapters RS3P4TF160F and RS3P4MF088F support the Intel Maintenance Free Backup Unit
AXXRMFBU7 accessory kit (also referred to as RMFBU in this document). During a power loss event, this
optional accessory provides back-up power to the Intel RAID adapter, allowing the adapter to offload the
data stored in the onboard cache to its onboard non-volatile NAND flash.
Benefits of the RMFBU option include:
•
Capacitor technology has a longer usable life span than batteries; also, reduces maintenance and
replacement costs.
•
Capacitors do not have the chemical volatility of batteries, which carry a risk of exothermic events.
•
RMFBU options do not require the comprehensive certifications needed for batteries for import and
export.
•
The RMFBU can constantly maintain the RAID volume in write-back mode even when doing learn
cycles.
•
The recharge rate of the super capacitor is minutes as compared to hours for a battery.
See
Chapter 8
