EFM32WG Datasheet, PDF (174/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

...the world's most energy friendly microcontrollers
• Programmable bus timing (frequency, setup and hold timing)
• Individual active high / active low setting of interface control signals
• Frame buffer can be either on-chip or off-chip
• Alpha-blending and masking
14.3 Functional Description
An overview of the EBI module is shown in Figure 14.1 (p. 175) . The EBI module consists of two
submodules. The first submodule implements a generic external device interface to for example SRAM
or Flash devices. The second submodule implements a TFT RGB interface which can be used together
with the generic external device interface to perform TFT Direct Drive from an external framebuffer to
a TFT display.
The EBI has multiplexed and non-multiplexed addressing modes. Fastest operation is achieved when
using a non-multiplexed addressing mode. The multiplexed addressing modes are somewhat slower
and require an external latch, but they use a significantly lower number of pins. The use of the 16 EBI_AD
pin connections depends on the addressing mode. They are used for both address and data in the
multiplexed modes. Also for the non-multiplexed 8-bit address mode both the address and data fit into
these 16 EBI_AD pins. If more address bits or data bits are needed, external latches can be used to
support up to 24-bit addresses or 16-bit data in the multiplexed addressing modes using only the 16
EBI_AD pins. Furthermore, independent of the addressing mode, up to 28 non-multiplexed address lines
can be enabled on the EBI_A pin connections.
When a read operation is requested by the Cortex-M4 or DMA via the EBI's AHB interface, the address
is transferred onto the EBI_AD and/or EBI_A bus. After a specific number of cycles, the EBI_REn pin
is activated and data is read from the EBI_AD bus. When a write operation is requested, the address
is transferred onto the EBI_AD and/or EBI_A bus and subsequently the write data is transferred onto
the EBI_AD bus as the EBI_WEn pin is activated. The detailed operation in the supported modes is
presented in the following sections.
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