AT91SAM7A3-AU Atmel, AT91SAM7A3-AU Datasheet - Page 37

• Manufacturer Part Number: AT91SAM7A3-AU
• Description: IC ARM7 MCU FLASH 256K 100LQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7A3-AU

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 60MHz
• Connectivity: CAN, I²C, MMC, SPI, SSC, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 62
• 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: 100-LQFP
• Controller Family/series: AT91SAM7xx
• No. Of I/o's: 62
• Ram Memory Size: 32KB
• Cpu Speed: 60MHz
• No. Of Timers: 3
• Rohs Compliant: Yes
• Package: 100LQFP
• Device Core: ARM7TDMI
• Family Name: 91S
• Maximum Speed: 60 MHz
• Operating Supply Voltage: 3.3 V
• Data Bus Width: 32 Bit
• Number Of Programmable I/os: 62
• Interface Type: CAN/SPI/I2S/TWI/USART/USB
• On-chip Adc: 2(8-chx10-bit)
• Number Of Timers: 3
• Processor Series: AT91SAMx
• Core: ARM7TDMI
• Data Ram Size: 32 KB
• Maximum Clock Frequency: 60 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: JTRACE-ARM-2M, MDK-ARM, RL-ARM, ULINK2
• Development Tools By Supplier: AT91SAM-ICE, AT91-ISP, AT91SAM7A3-EK
• Minimum Operating Temperature: - 40 C
• Cpu Family: 91S
• Device Core Size: 32b
• Frequency (max): 60MHz
• Total Internal Ram Size: 32KB
• # I/os (max): 62
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (max): 3.6V
• Operating Supply Voltage (min): 3V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 100
• Package Type: LQFP
• For Use With: AT91SAM-ICE - EMULATOR FOR AT91 ARM7/ARM9AT91SAM7A3-EK - KIT EVAL FOR AT91SAM7A3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

12.2.4.1
12.2.4.2
12.2.4.3
6042E–ATARM–14-Dec-06
Modes and Exception Handling
Status Registers
Exception Types
Registers R0 to R7 are unbanked registers. This means that each of them refers to the same
32-bit physical register in all processor modes. They are general-purpose registers, with no
special uses managed by the architecture, and can be used wherever an instruction allows a
general-purpose register to be specified.
Registers R8 to R14 are banked registers. This means that each of them depends on the cur-
rent mode of the processor.
All exceptions have banked registers for R14 and R13.
After an exception, R14 holds the return address for exception processing. This address is
used to return after the exception is processed, as well as to address the instruction that
caused the exception.
R13 is banked across exception modes to provide each exception handler with a private stack
pointer.
The fast interrupt mode also banks registers 8 to 12 so that interrupt processing can begin
without having to save these registers.
A seventh processing mode, System Mode, does not have any banked registers. It uses the
User Mode registers. System Mode runs tasks that require a privileged processor mode and
allows them to invoke all classes of exceptions.
All other processor states are held in status registers. The current operating processor status
is in the Current Program Status Register (CPSR). The CPSR holds:
All five exception modes also have a Saved Program Status Register (SPSR) that holds the
CPSR of the task immediately preceding the exception.
The ARM7TDMI
type. The types of exceptions are:
Exceptions are generated by internal and external sources.
More than one exception can occur in the same time.
When an exception occurs, the banked version of R14 and the SPSR for the exception mode
are used to save state.
• four ALU flags (Negative, Zero, Carry, and Overflow)
• two interrupt disable bits (one for each type of interrupt)
• one bit to indicate ARM or Thumb execution
• five bits to encode the current processor mode
• fast interrupt (FIQ)
• normal interrupt (IRQ)
• memory aborts (used to implement memory protection or virtual memory)
• attempted execution of an undefined instruction
• software interrupts (SWIs)
supports five types of exception and a privileged processing mode for each
AT91SAM7A3 Preliminary
37