AT91SAM7SE256B-CUR Atmel, AT91SAM7SE256B-CUR Datasheet - Page 165

• Manufacturer Part Number: AT91SAM7SE256B-CUR
• Description: IC ARM7 MCU FLASH 256K 128-LQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7SE256B-CUR

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 55MHz
• Connectivity: EBI/EMI, I²C, SPI, SSC, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 88
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Processor Series: SAM7SE256
• Core: ARM7TDMI
• Data Bus Width: 32 bit
• Data Ram Size: 32 KB
• Interface Type: SPI, USB
• Maximum Clock Frequency: 48 MHz
• Number Of Programmable I/os: 88
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Operating Temperature Range: - 40 C to + 85 C
• Processor To Be Evaluated: AT91SAM7SE256B
• Supply Current (max): 60 uA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

22.6.2
22.6.2.1
22.6.2.2
6222F–ATARM–14-Jan-11
Write Access
Write Access Type
Byte Write Access
Figure 22-5. Memory Connection for a 16-bit Data Path Device
Each chip select with a 16-bit data bus can operate with one of two different types of write
access:
This option is controlled by the BAT field in the SMC_CSR for the corresponding chip select.
See
Byte Write Access is used to connect 2 x 8-bit devices as a 16-bit memory page.
Figure 22-6
• Byte Write Access supports two byte write and a single read signal.
• Byte Select Access selects upper and/or lower byte with two byte select lines, and separate
• The signal A0/NLB is not used.
• The signal NWR1/NUB is used as NWR1 and enables upper byte writes.
• The signal NWR0/NWE is used as NWR0 and enables lower byte writes.
• The signal NRD enables half-word and byte reads.
read and write signals.
“SMC Chip Select Registers” on page
shows how to connect two 512K x 8-bit devices in parallel on NCS2 (BAT = 0)
SMC
D[15:8]
A[22:1]
D[7:0]
NCS2
NWE
NRD
NUB
NLB
SAM7SE512/256/32 Preliminary
196.
D[7:0]
D[15:8]
A[22:0]
Low Byte Enable
High Byte Enable
Write Enable
Output Enable
Memory Enable
165