Publication No. PPC11A-HRM/1
Functional Description 35
For further details of these protection mechanisms, see the S29GL Flash Family data
sheet.
Software can detect the setting (fitted or not fitted) of the
Jumper Link Status Register (offset 0x6CD)
.
4.6
SPI Serial Recovery Flash
An 8 MB Micron N25Q064A11EF640 SPI serial Flash device is connected on the SPI
interface of the processor. This provides storage for recovery boot. The SPI serial
Flash is protected by default and cannot be unprotected by the user.
4.7
NAND Flash Solid State Drive
The PPC11A optionally provides an on-board 32 GB NAND Flash Solid State Drive
(SSD). The device used is a Silicon Motion SM651GEB SATA NANDrive device
connected to a SATA port of a Marvell PCIe to SATA controller. This device is an
SLC-mode type, which is MLC technology operating to give similar endurance and
retention as pure SLC operation. Alternative devices sizes and Flash technologies are
available.
LINK
For more details on the SSD, see
http://www.siliconmotion.com
.
The SSD may be write-protected using an output from the EEPROM
. Software is also able to trigger a fast erase of the device using an FPGA
register.
4.8
NVSRAM
The PPC11A has 512 KB of non-volatile SRAM for configuration data storage and
general-purpose use. This functionality is implemented using an 8-bit wide Cypress
CY14V104LA-BA45XI NVRAM device. This has unlimited read/write endurance and
stated data retention is greater than 20 years at 85°C.
CS2 on the processor’s Local Bus Controller is used to access the NVRAM, which can
be read from and written to in the same way as standard RAM.
The NVRAM is write-enabled when the