ST STM32F0 Series User Manual

PM0215 The STM32 Cortex-M0 instruction set
Doc ID 022979 Rev 1 49/91
3.5.1 ADD{S}, ADCS, SUB{S}, SBCS, and RSBS
Add, add with carry, subtract, subtract with carry, and reverse subtract.
Syntax
ADCS {Rd,} Rn, Rm
ADD{S} {Rd,} Rn, <Rm|#imm>
RSBS {Rd,} Rn, Rm, #0
SBCS {Rd,} Rn, Rm
SUB{S} {Rd,} Rn, <Rm|#imm>
where:
● S: causes an ADD or SUB instruction to update flags
● Rd: specifies the result register. If omitted,this value is assumed to take the same value
as Rn, for example ADDS R1,R2 is identical to ADDS R1,R1,R2.
● Rn: specifies the first source register
● Rm: specifies the second source register
● imm: specifies a constant immediate value.
Operation
The ADCS instruction adds the value in Rn to the value in Rm, adding a further one if the
carry flag is set, places the result in the register specified by Rd and updates the N, Z, C,
and V flags.
The ADD instruction adds the value in Rn to the value in Rm or an immediate value
specified by imm and places the result in the register specified by Rd.
The ADDS instruction performs the same operation as ADD and also updates the N, Z, C
and V flags.
The RSBS instruction subtracts the value in Rn from zero, producing the arithmetic negative
of the value, and places the result in the register specified by Rd and updates the N, Z, C
and V flags.
The SBCS instruction subtracts the value of Rm from the value in Rn, deducts a further one
if the carry flag is set. It places the result in the register specified by Rd and updates the N,
Z, C and V flags.
The SUB instruction subtracts the value in Rm or the immediate specified by imm. It places
the result in the register specified by Rd.
The SUBS instruction performs the same operation as SUB and also updates the N, Z, C
and V flags.
Use ADC and SBC to synthesize multiword arithmetic (see Multiword arithmetic examples
on page 50 and ADR on page 42).
Restrictions
Tabl e 20 lists the legal combinations of register specifiers and immediate values that can be
used with each instruction.

ST STM32F0 Series Specifications

General

Series	STM32F0
Core	ARM Cortex-M0
Operating Frequency	Up to 48 MHz
Flash Memory	16 KB to 256 KB
SRAM	4 KB to 32 KB
ADC Resolution	12-bit
ADC Channels	Up to 16
Operating Voltage	2.0 V to 3.6 V
DAC Resolution	12-bit (some series)
Communication Interfaces	I2C, SPI, USART, USB, CAN
Operating Temperature	-40°C to 85°C
Package Options	LQFP, TSSOP, UFQFPN, WLCSP

Summary

Introduction to STM32F0xxx Programming

About this document

1.1 Typographical conventions

Defines typographical conventions used in the document.

1.2 List of abbreviations for registers

Lists abbreviations used for register descriptions.

1.3 About the STM32 Cortex-M0 processor and core peripherals

Overview of the Cortex-M0 processor and its core peripherals.

The STM32 Cortex-M0 processor

2.1 Programmers model

Describes the Cortex-M0 programmer's model, modes, and stacks.

2.2 Memory model

Details the processor memory map and memory access behavior.

2.3 Exception model

Explains the exception model, states, types, and priorities.

2.4 Fault handling

Covers fault handling mechanisms, including lockup states.

2.5 Power management

Describes sleep and deep sleep modes for power saving.

The STM32 Cortex-M0 instruction set

3.1 Instruction set summary

Summarizes the Thumb instruction set supported by the Cortex-M0.

3.4 Memory access instructions

Covers instructions for loading and storing data from/to memory.

3.5 General data processing instructions

Describes instructions for arithmetic, logical, and data manipulation operations.

3.6 Branch and control instructions

Details instructions for program flow control and branching.

Core peripherals

4.1 About the STM32 Cortex-M0 core peripherals

Introduces the core peripherals and their address map.

4.2 Nested vectored interrupt controller (NVIC)

Details the NVIC's support for interrupts and its registers.

4.3 System control block (SCB)

Describes the SCB for system implementation information and control.

4.4 SysTick timer (STK)

Explains the SysTick timer's functionality and registers.

Revision history