User manual

...the world's most energy friendly microcontrollers
2012-04-24 - Giant Gecko Family - d0053_Rev0.96 3
www.energymicro.com
2 About This Document
This document contains reference material for the EFM32GG series of microcontrollers. All modules
and peripherals in the EFM32GG series devices are described in general terms. Not all modules are
present in all devices and the feature set for each device might vary. Such differences, including pinout,
are covered in the device-specific datasheets.
2.1 Conventions
Register Names
Register names are given with a module name prefix followed by the short register name:
TIMERn_CTRL - Control Register
The "n" denotes the module number for modules which can exist in more than one instance.
Some registers are grouped which leads to a group name following the module prefix:
GPIO_Px_DOUT - Port Data Out Register
The "x" denotes the port instance (A,B,...)
Bit Fields
Registers contain one or more bit fields which can be 1 to 32 bits wide. Bit fields wider than 1 bit are
given with start and stop bit (x:y).
Address
The address for each register can be found by adding the modules base address (found in Memory
Map), with the offset address for the register (found in module Register Map).
Access Type
The register access types used in the register descriptions are explained in Table 2.1 (p. 3) .
Table 2.1. Register Access Types
Access Type Description
R Read only. Writes are ignored
RW Readable and writable
RW1 Readable and writable. Only writes to 1 have effect
W1 Read value undefined. Only writes to 1 have effect
W Write only. Read value undefined.
RWH Readable, writable and updated by hardware
Number format
0x prefix is used for hexadecimal numbers
0b prefix is used for binary numbers
Numbers without prefix are in decimal representation.
Reserved