UPD70F3201YGC-YEU-A Renesas Electronics America, UPD70F3201YGC-YEU-A Datasheet - Page 57

• Manufacturer Part Number: UPD70F3201YGC-YEU-A
• Description: MCU 32BIT I2C 100TQFP
• Manufacturer: Renesas Electronics America
• Series: V850ES/Sx2r

Specifications of UPD70F3201YGC-YEU-A

• Core Processor: RISC
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: CSI, EBI/EMI, I²C, UART/USART
• Peripherals: DMA, PWM, WDT
• Number Of I /o: 68
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 2.2 V ~ 2.7 V
• Data Converters: A/D 12x10b; D/A 2x8b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

3.2.1
r0
r1
r2
r3
r4
r5
r6 to r29
r30
r31
PC
The program registers include general-purpose registers and a program counter.
(1) General-purpose registers (r0 to r31)
(2) Program counter (PC)
Name
Thirty-two general-purpose registers, r0 to r31, are available. Any of these registers can be used to store a
data variable or an address variable.
However, r0 and r30 are implicitly used by instructions and care must be exercised when these registers are
used. r0 always holds 0 and is used for an operation that uses 0 or addressing of offset 0. r30 is used by the
SLD and SST instructions as a base pointer when these instructions access the memory. r1, r3 to r5, and r31
are implicitly used by the assembler and C compiler. When using these registers, save their contents for
protection, and then restore the contents after using the registers. r2 is sometimes used by the real-time OS.
If the real-time OS does not use r2, it can be used as a register for variables.
The program counter holds the instruction address during program execution. The lower 32 bits of this register
are valid. Bits 31 to 26 are fixed to 0. A carry from bit 25 to 26 is ignored even if it occurs.
Bit 0 is fixed to 0. This means that execution cannot branch to an odd address.
PC
Program register set
Zero register
Assembler-reserved register
Register for address/data variable (if real-time OS does not use r2)
Stack pointer
Global pointer
Text pointer
Register for address/data variable
Element pointer
Link pointer
Program counter
31
Fixed to 0
26 25
Usage
Instruction address during program execution
Table 3-1. Program Registers
CHAPTER 3 CPU FUNCTION
User’s Manual U15905EJ2V1UD
Always holds 0.
Used as working register to create 32-bit immediate data
Used to create a stack frame when a function is called
Used to access a global variable in the data area
Used as register that indicates the beginning of a text area (area
where program codes are located)
Used as base pointer to access memory
Used when the compiler calls a function
Holds the instruction address during program execution
Operation
1 0
0
Default value
00000000H
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