a3p250l Actel Corporation, a3p250l Datasheet - Page 10

• Manufacturer Part Number: a3p250l
• Description: Proasic3l Low-power Flash Fpgas With Flash*freeze Technology
• Manufacturer: Actel Corporation

ProASIC3L Device Family Overview
1 -6
User Nonvolatile FlashROM
Actel ProASIC3L devices have 1 kbit of on-chip, user-accessible, nonvolatile FlashROM. The
FlashROM can be used in diverse system applications:
The FlashROM is written using the standard ProASIC3L IEEE 1532 JTAG programming interface.The
core can be individually programmed (erased and written), and on-chip AES decryption can be used
selectively to securely load data over public networks, as in security keys stored in the FlashROM for
a user design.
The FlashROM can be programmed via the JTAG programming interface, and its contents can be
read back either through the JTAG programming interface or via direct FPGA core addressing. Note
that the FlashROM can only be programmed from the JTAG interface and cannot be programmed
from the internal logic array.
The FlashROM is programmed as 8 banks of 128 bits; however, reading is performed on a byte-by-
byte basis using a synchronous interface. A 7-bit address from the FPGA core defines which of the 8
banks and which of the 16 bytes within that bank are being read. The three most significant bits
(MSBs) of the FlashROM address determine the bank, and the four least significant bits (LSBs) of
the FlashROM address define the byte.
The Actel ProASIC3L development software solutions, Libero IDE and Designer, have extensive
support for the FlashROM. One such feature is auto-generation of sequential programming files
for applications requiring a unique serial number in each part. Another feature allows the inclusion
of static data for system version control. Data for the FlashROM can be generated quickly and
easily using Actel Libero IDE and Designer software tools. Comprehensive programming file
support is also included to allow for easy programming of large numbers of parts with differing
FlashROM contents.
SRAM and FIFO
ProASIC3L devices have embedded SRAM blocks along their north and south sides. Each variable-
aspect-ratio SRAM block is 4,608 bits in size. Available memory configurations are 256×18, 512×9,
1k×4, 2k×2, and 4k×1 bits. The individual blocks have independent read and write ports that can be
configured with different bit widths on each port. For example, data can be sent through a 4-bit
port and read as a single bitstream. The embedded SRAM blocks can be initialized via the device
JTAG port (ROM emulation mode) using the UJTAG macro.
In addition, every SRAM block has an embedded FIFO control unit. The control unit allows the
SRAM block to be configured as a synchronous FIFO without using additional core VersaTiles. The
FIFO width and depth are programmable. The FIFO also features programmable Almost Empty
(AEMPTY) and Almost Full (AFULL) flags in addition to the normal Empty and Full flags. The
embedded FIFO control unit contains the counters necessary for generation of the read and write
address pointers. The embedded SRAM/FIFO blocks can be cascaded to create larger configurations.
PLL and CCC
ProASIC3L devices provide designers with flexible clock conditioning circuit (CCC) capabilities. Each
member of the ProASIC3L family contains six CCCs. One CCC (center west side) has a PLL.
The six CCC blocks are located at the four corners and the centers of the east and west sides. One
CCC (center west side) has a PLL.
All six CCC blocks are usable; the four corner CCCs and the east CCC allow simple clock delay
operations as well as clock spine access.
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Internet Protocol addressing (wireless or fixed)
System calibration settings
Device serialization and/or inventory control
Subscription-based business models (for example, set-top boxes)
Secure key storage for secure communications algorithms
Asset management/tracking
Date stamping
Version management
v1.1