Altera Cyclone III Development Board - Manual (Page 64)

2–54 Chapter 2: Board Components
On-Board Memory
Cyclone III 3C120 Development Board Reference Manual © March 2009 Altera Corporation
SRAM
The board features 8 MB of SRAM memory with a 32-bit data bus. The devices use
1.8-V CMOS signaling and are optimized for low cost and power.
The 32-bit interface comprises two ×16 devices. The Samsung part features a
maximum frequency of 104 MHz (104 Mbps). The theoretical bandwidth of the entire
interface is 416 Mbps.
The SRAM devices are part of a shared bus with connectivity to the MAX II CPLD as
well as the flash memory, which is called the FSM bus. All three devices use 1.8-V
CMOS signaling. Altera recommends using the 50-
Ω OCT setting on the FPGA and
the one-half drive setting on the SRAM.
Table 2–53 lists the SRAM interface signal name, description, and I/O standard.
Signal name and type are relative to the Cyclone III device, i.e., I/O setting and
direction.
Table 2–53. SRAM Interface I/O (Part 1 of 3)
Board
Reference Description I/O Standard
Schematic Signal
Name
Cyclone III
Device Pin
Number
U23 pin A1 Byte enables bit 0 1.8 V SRAM_BEn0 AF20
U23 pin B2 Byte enables bit 1 1.8 V SRAM_BEn1 AH26
U24 pin A1 Byte enables bit 2 1.8 V SRAM_BEn2 AE22
U24 pin B2 Byte enables bit 3 1.8 V SRAM_BEn3 AB21
U23, U24 pin J2 Clock (drives two memories) 1.8 V SRAM_CLK AD22
U23, U24 pin B5 Chip select 1.8 V SRAM_CSn AB19
U23, U24 pin A2 Output enable 1.8 V SRAM_OEn AD25
U23, U24 pin A6 Power save /MRS set pin 1.8 V SRAM_PSn B4
U23 pin J1 Data wait bit 0 1.8 V SRAM_WAIT0 AG15
U24 pin J1 Data wait bit 1 1.8 V SRAM_WAIT1 AH25
U23, U24 pin G5 Write enable 1.8 V SRAM_WEn AE25
U23, U24 pin J3 Address valid 1.8 V SRAM_ADVn AA19
U23, U24 pin A3 Address bit 1 (DWORD aligned) 1.8 V FSA1 AH10
U23, U24 pin A4 Address bit 2 (DWORD aligned) 1.8 V FSA2 AA13
U23, U24 pin A5 Address bit 3 (DWORD aligned) 1.8 V FSA3 AC10
U23, U24 pin B3 Address bit 4 (DWORD aligned) 1.8 V FSA4 Y15
U23, U24 pin B4 Address bit 5 (DWORD aligned) 1.8 V FSA5 AF22
U23, U24 pin C3 Address bit 6 (DWORD aligned) 1.8 V FSA6 AF26
U23, U24 pin C4 Address bit 7 (DWORD aligned) 1.8 V FSA7 AF4
U23, U24 pin D4 Address bit 8 (DWORD aligned) 1.8 V FSA8 AD8
U23, U24 pin H2 Address bit 9 (DWORD aligned) 1.8 V FSA9 AG26
U23, U24 pin H3 Address bit 10 (DWORD aligned) 1.8 V FSA10 AH6
U23, U24 pin H4 Address bit 11 (DWORD aligned) 1.8 V FSA11 AD24
U23, U24 pin H5 Address bit 12 (DWORD aligned) 1.8 V FSA12 AF9
U23, U24 pin G3 Address bit 13 (DWORD aligned) 1.8 V FSA13 AA8