User's Manual
Table Of Contents
- Cover
- Notice
- General Precautions in the Handling of Microprocessing Unit and Microcontroller Unit Products
- How to Use This Manual
- Contents
- Features
- 1. Overview
- 2. CPU
- 2.1 Features
- 2.2 Register Set of the CPU
- 2.2.1 General-Purpose Registers (R0 to R15)
- 2.2.2 Control Registers
- 2.2.2.1 Interrupt Stack Pointer (ISP)/User Stack Pointer (USP)
- 2.2.2.2 Exception Table Register (EXTB)
- 2.2.2.3 Interrupt Table Register (INTB)
- 2.2.2.4 Program Counter (PC)
- 2.2.2.5 Processor Status Word (PSW)
- 2.2.2.6 Backup PC (BPC)
- 2.2.2.7 Backup PSW (BPSW)
- 2.2.2.8 Fast Interrupt Vector Register (FINTV)
- 2.2.2.9 Floating-Point Status Word (FPSW)
- 2.2.3 Accumulator
- 2.3 Processor Mode
- 2.4 Data Types
- 2.5 Endian
- 2.6 Vector Table
- 2.7 Operation of Instructions
- 2.8 Number of Cycles
- 3. Operating Modes
- 4. Address Space
- 5. I/O Registers
- 6. Resets
- 7. Option-Setting Memory (OFSM)
- 8. Voltage Detection Circuit (LVDAb)
- 9. Clock Generation Circuit
- 9.1 Overview
- 9.2 Register Descriptions
- 9.2.1 System Clock Control Register (SCKCR)
- 9.2.2 System Clock Control Register 3 (SCKCR3)
- 9.2.3 PLL Control Register (PLLCR)
- 9.2.4 PLL Control Register 2 (PLLCR2)
- 9.2.5 USB-dedicated PLL Control Register (UPLLCR)
- 9.2.6 USB-dedicated PLL Control Register 2 (UPLLCR2)
- 9.2.7 Main Clock Oscillator Control Register (MOSCCR)
- 9.2.8 Sub-Clock Oscillator Control Register (SOSCCR)
- 9.2.9 Low-Speed On-Chip Oscillator Control Register (LOCOCR)
- 9.2.10 IWDT-Dedicated On-Chip Oscillator Control Register (ILOCOCR)
- 9.2.11 High-Speed On-Chip Oscillator Control Register (HOCOCR)
- 9.2.12 High-Speed On-Chip Oscillator Control Register 2 (HOCOCR2)
- 9.2.13 Oscillation Stabilization Flag Register (OSCOVFSR)
- 9.2.14 Oscillation Stop Detection Control Register (OSTDCR)
- 9.2.15 Oscillation Stop Detection Status Register (OSTDSR)
- 9.2.16 Main Clock Oscillator Wait Control Register (MOSCWTCR)
- 9.2.17 CLKOUT Output Control Register (CKOCR)
- 9.2.18 Main Clock Oscillator Forced Oscillation Control Register (MOFCR)
- 9.2.19 Memory Wait Cycle Setting Register (MEMWAIT)
- 9.2.20 Low-Speed On-Chip Oscillator Trimming Register (LOCOTRR)
- 9.2.21 IWDT-Dedicated On-Chip Oscillator Trimming Register (ILOCOTRR)
- 9.2.22 High-Speed On-Chip Oscillator Trimming Register n (HOCOTRRn) (n = 0, 3)
- 9.3 Main Clock Oscillator
- 9.4 Sub-Clock Oscillator
- 9.5 Dedicated Clock Oscillator for Bluetooth
- 9.6 Oscillation Stop Detection Function
- 9.7 PLL Circuit
- 9.8 Internal Clock
- 9.9 Usage Notes
- 10. Clock Frequency Accuracy Measurement Circuit (CAC)
- 10.1 Overview
- 10.2 Register Descriptions
- 10.2.1 CAC Control Register 0 (CACR0)
- 10.2.2 CAC Control Register 1 (CACR1)
- 10.2.3 CAC Control Register 2 (CACR2)
- 10.2.4 CAC Interrupt Request Enable Register (CAICR)
- 10.2.5 CAC Status Register (CASTR)
- 10.2.6 CAC Upper-Limit Value Setting Register (CAULVR)
- 10.2.7 CAC Lower-Limit Value Setting Register (CALLVR)
- 10.2.8 CAC Counter Buffer Register (CACNTBR)
- 10.3 Operation
- 10.4 Interrupt Requests
- 10.5 Usage Notes
- 11. Low Power Consumption
- 11.1 Overview
- 11.2 Register Descriptions
- 11.2.1 Standby Control Register (SBYCR)
- 11.2.2 Module Stop Control Register A (MSTPCRA)
- 11.2.3 Module Stop Control Register B (MSTPCRB)
- 11.2.4 Module Stop Control Register C (MSTPCRC)
- 11.2.5 Module Stop Control Register D (MSTPCRD)
- 11.2.6 Operating Power Control Register (OPCCR)
- 11.2.7 Sub Operating Power Control Register (SOPCCR)
- 11.2.8 Sleep Mode Return Clock Source Switching Register (RSTCKCR)
- 11.3 Reducing Power Consumption by Switching Clock Signals
- 11.4 Module Stop Function
- 11.5 Function for Lower Operating Power Consumption
- 11.6 Low Power Consumption Modes
- 11.7 Usage Notes
- 12. Battery Backup Function
- 13. Register Write Protection Function
- 14. Exception Handling
- 15. Interrupt Controller (ICUb)
- 15.1 Overview
- 15.2 Register Descriptions
- 15.2.1 Interrupt Request Register n (IRn) (n = interrupt vector number)
- 15.2.2 Interrupt Request Enable Register m (IERm) (m = 02h to 1Fh)
- 15.2.3 Interrupt Source Priority Register n (IPRn) (n = interrupt vector number)
- 15.2.4 Fast Interrupt Set Register (FIR)
- 15.2.5 Software Interrupt Generation Register (SWINTR)
- 15.2.6 DTC Transfer Request Enable Register n (DTCERn) (n = interrupt vector number)
- 15.2.7 DMAC Trigger Select Register m (DMRSRm) (m = DMAC channel number)
- 15.2.8 IRQ Control Register i (IRQCRi) (i = 0, 1, and 4 to 7)
- 15.2.9 IRQ Pin Digital Filter Enable Register 0 (IRQFLTE0)
- 15.2.10 IRQ Pin Digital Filter Setting Register 0 (IRQFLTC0)
- 15.2.11 Non-Maskable Interrupt Status Register (NMISR)
- 15.2.12 Non-Maskable Interrupt Enable Register (NMIER)
- 15.2.13 Non-Maskable Interrupt Status Clear Register (NMICLR)
- 15.2.14 NMI Pin Interrupt Control Register (NMICR)
- 15.2.15 NMI Pin Digital Filter Enable Register (NMIFLTE)
- 15.2.16 NMI Pin Digital Filter Setting Register (NMIFLTC)
- 15.3 Vector Table
- 15.4 Interrupt Operation
- 15.5 Non-maskable Interrupt Operation
- 15.6 Return from Power-Down States
- 15.7 Usage Note
- 16. Buses
- 17. Memory-Protection Unit (MPU)
- 17.1 Overview
- 17.2 Register Descriptions
- 17.2.1 Region-n Start Page Number Register (RSPAGEn) (n = 0 to 7)
- 17.2.2 Region-n End Page Number Register (REPAGEn) (n = 0 to 7)
- 17.2.3 Memory-Protection Enable Register (MPEN)
- 17.2.4 Background Access Control Register (MPBAC)
- 17.2.5 Memory-Protection Error Status-Clearing Register (MPECLR)
- 17.2.6 Memory-Protection Error Status Register (MPESTS)
- 17.2.7 Data Memory-Protection Error Address Register (MPDEA)
- 17.2.8 Region Search Address Register (MPSA)
- 17.2.9 Region Search Operation Register (MPOPS)
- 17.2.10 Region Invalidation Operation Register (MPOPI)
- 17.2.11 Instruction-Hit Region Register (MHITI)
- 17.2.12 Data-Hit Region Register (MHITD)
- 17.3 Functions
- 17.4 Procedures for Using Memory Protection
- 18. DMA Controller (DMACA)
- 18.1 Overview
- 18.2 Register Descriptions
- 18.2.1 DMA Source Address Register (DMSAR)
- 18.2.2 DMA Destination Address Register (DMDAR)
- 18.2.3 DMA Transfer Count Register (DMCRA)
- 18.2.4 DMA Block Transfer Count Register (DMCRB)
- 18.2.5 DMA Transfer Mode Register (DMTMD)
- 18.2.6 DMA Interrupt Setting Register (DMINT)
- 18.2.7 DMA Address Mode Register (DMAMD)
- 18.2.8 DMA Offset Register (DMOFR)
- 18.2.9 DMA Transfer Enable Register (DMCNT)
- 18.2.10 DMA Software Start Register (DMREQ)
- 18.2.11 DMA Status Register (DMSTS)
- 18.2.12 DMA Activation Source Flag Control Register (DMCSL)
- 18.2.13 DMA Module Activation Register (DMAST)
- 18.3 Operation
- 18.4 Ending DMA Transfer
- 18.5 Interrupts
- 18.6 Event Link Function
- 18.7 Low Power Consumption Function
- 18.8 Usage Notes
- 18.8.1 DMA Transfer to Peripheral Modules
- 18.8.2 Access to the Registers during DMA Transfer
- 18.8.3 DMA Transfer to Reserved Areas
- 18.8.4 Interrupt Request by the DMA Activation Source Flag Control Register (DMCSL) at the End of each Transfer
- 18.8.5 Setting of DMAC Activation Source Select Register of the Interrupt Controller (ICU.DMRSRm)
- 18.8.6 Suspending or Restarting DMA Activation
- 19. Data Transfer Controller (DTCa)
- 19.1 Overview
- 19.2 Register Descriptions
- 19.2.1 DTC Mode Register A (MRA)
- 19.2.2 DTC Mode Register B (MRB)
- 19.2.3 DTC Transfer Source Register (SAR)
- 19.2.4 DTC Transfer Destination Register (DAR)
- 19.2.5 DTC Transfer Count Register A (CRA)
- 19.2.6 DTC Transfer Count Register B (CRB)
- 19.2.7 DTC Control Register (DTCCR)
- 19.2.8 DTC Vector Base Register (DTCVBR)
- 19.2.9 DTC Address Mode Register (DTCADMOD)
- 19.2.10 DTC Module Start Register (DTCST)
- 19.2.11 DTC Status Register (DTCSTS)
- 19.3 Request Sources
- 19.4 Operation
R01UH0823EJ0110 Rev.1.10 Page 326 of 1852
Nov 30, 2020
RX23W Group 17. Memory-Protection Unit (MPU)
17. Memory-Protection Unit (MPU)
17.1 Overview
The RXv2 CPU incorporates a memory-protection unit that checks the addresses of CPU access to the overall address
space (0000 0000h to FFFF FFFFh).
Access-control information can be set for up to eight regions, and permission for access to each region is in accord with
this information. The default response to the detection of access to a region where permission has not been set is the
generation of a memory-protection error.
The supported access-control information for the individual regions consists of permission to read, permission to write,
and permission to execute. This access-control information is effective when the processor mode of the CPU is user
mode. Memory protection is not applied when the CPU is in supervisor mode.
Table 17.1 lists the specifications of the memory-protection unit, and Figure 17.1 shows a block diagram of the
memory-protection unit.
Table 17.1 Specifications of Memory Protection
Specifictaions Description
Region to be covered by memory protection
and processor mode
0000 0000h to FFFF FFFFh (in user mode)
No memory protection in supervisor mode
Number of regions 8
Page size (smallest unit of protection) 16 bytes
Specifying addresses of individual regions Setting the page numbers where regions start and end
Setting to make memory protection effective
or ineffective in individual regions
A V (valid) bit in each region-n end page number register (REPAGEn) makes the
settings effective or ineffective for the corresponding region (n = 0 to 7).
Access-control information settings for
individual regions
Instruction execution: Permission to execute
Operand access: Permission to read, permission to write
Start of memory-protection operations After the memory-protection unit has been enabled, access monitoring starting up with
the transition to user mode.
Memory-protection error processing Generation of access exceptions
Addresses where memory-protection errors
are generated
Address in instruction execution: The PC value is preserved on the stack.
Address in operand access: The address is stored in the data memory-protection error
address register (MPDEA).
Determining the reasons for memory-
protection errors
The memory-protection error status register (MPESTS) holds indicators of the reason.
Background region setting Access-control information can be set for the background region (the whole address
space).
Processing where regions overlap The access-control information for access to an overlap between regions is the logical
OR of the attributes for the given regions, and permission is given priority.