R8A77800ANBGAV Renesas Electronics America, R8A77800ANBGAV Datasheet - Page 86

• Manufacturer Part Number: R8A77800ANBGAV
• Description: IC SUPERH MPU ROMLESS 449-BGA
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7780r

Specifications of R8A77800ANBGAV

• Core Processor: SH-4A
• Core Size: 32-Bit
• Speed: 400MHz
• Connectivity: Audio Codec, MMC, Serial Sound, SCI, SIO, SPI, SSI
• Peripherals: DMA, POR, WDT
• Number Of I /o: 75
• Program Memory Type: ROMless
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.15 V ~ 1.35 V
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 449-BGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

Section 2 Programming Model
2.2
2.2.1
Processing Modes: This LSI has two processing modes, user mode and privileged mode. This
LSI normally operates in user mode, and switches to privileged mode when an exception occurs or
an interrupt is accepted. There are four kinds of registers—general registers, system registers,
control registers, and floating-point registers—and the registers that can be accessed differ in the
two processing modes.
General Registers: There are 16 general registers, designated R0 to R15. General registers R0 to
R7 are banked registers which are switched by a processing mode change.
• Privileged mode
• User mode
Control Registers: Control registers comprise the global base register (GBR) and status register
(SR), which can be accessed in both processing modes, and the saved status register (SSR), saved
program counter (SPC), vector base register (VBR), saved general register 15 (SGR), and debug
base register (DBR), which can only be accessed in privileged mode. Some bits of the status
register (such as the RB bit) can only be accessed in privileged mode.
System Registers: System registers comprise the multiply-and-accumulate registers
(MACH/MACL), the procedure register (PR), and the program counter (PC). Access to these
registers does not depend on the processing mode.
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In privileged mode, the register bank bit (RB) in the status register (SR) defines which banked
register set is accessed as general registers, and which set is accessed only through the load
control register (LDC) and store control register (STC) instructions.
When the RB bit is 1 (that is, when bank 1 is selected), the 16 registers comprising bank 1
general registers R0_BANK1 to R7_BANK1 and non-banked general registers R8 to R15 can
be accessed as general registers R0 to R15. In this case, the eight registers comprising bank 0
general registers R0_BANK0 to R7_BANK0 are accessed by the LDC/STC instructions.
When the RB bit is 0 (that is, when bank 0 is selected), the 16 registers comprising bank 0
general registers R0_BANK0 to R7_BANK0 and non-banked general registers R8 to R15 can
be accessed as general registers R0 to R15. In this case, the eight registers comprising bank 1
general registers R0_BANK1 to R7_BANK1 are accessed by the LDC/STC instructions.
In user mode, the 16 registers comprising bank 0 general registers R0_BANK0 to R7_BANK0
and non-banked general registers R8 to R15 can be accessed as general registers R0 to R15.
The eight registers comprising bank 1 general registers R0_BANK1 to R7_BANK1 cannot be
accessed.
Register Descriptions
Privileged Mode and Banks