EFM32G200F64 Energy Micro, EFM32G200F64 Datasheet - Page 132

• Manufacturer Part Number: EFM32G200F64
• Description: MCU 32BIT 64KB FLASH 32-QFN
• Manufacturer: Energy Micro
• Series: Geckor

Specifications of EFM32G200F64

• Core Processor: ARM® Cortex-M3™
• Core Size: 32-Bit
• Speed: 32MHz
• Connectivity: EBI/EMI, I²C, IrDA, SmartCard, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 24
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.8 V
• Data Converters: A/D 4x12b, D/A 1x12b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-VQFN Exposed Pad
• Processor Series: EFM32G200
• Core: ARM Cortex-M3
• Data Bus Width: 32 bit
• Data Ram Size: 16 KB
• Interface Type: I2C, UART
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 2
• Operating Supply Voltage: 1.8 V to 3.8 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

14 EBI - External Bus Interface
14.1 Introduction
14.2 Features
14.3 Functional Description
2010-09-06 - d0001_Rev1.00
The External Bus Interface provides access to external parallel interface devices such as SRAM, FLASH,
ADCs and LCDs. The interface is memory mapped into the address bus of the Cortex-M3. This enables
seamless access from software without manually manipulating the IO settings each time a read or write
is performed. The data and address lines are multiplexed in order to reduce the number of pins required
to interface the external devices. The timing is adjustable to meet specifications of the external devices.
The interface is limited to asynchronous devices.
• Multiplexed data and address lines for reduced pin count
• Up to 24-bit address width
• Up to 16-bit data width
• 8-bit true parallel operation
• 4 memory bank regions with individual chip select lines (EBI_CSn)
• Accurate control of setup, strobe, hold and turn-around timing
• Individual active high / active low setting of interface control signals
• Slave read/write cycle extension
An overview of the EBI module is shown in Figure 14.1 (p. 133) . The EBI has 16 pin connections
which can be used for both address and data. In 8-bit address mode, the address and data both fit into
these 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. When a read operation is requested by the AHB interface, the address is
transferred onto the EBI_AD bus. After a specific number of cycles, the EBI_REn pin is activated and data
0 1 2 3
4
(EFM32)
EBI
Parallel Interface
External
Async.
Device
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132
What?
The EBI is used for accessing external
parallel devices. The devices appear as a
part of the EFM32G's internal memory map
and are therefore extremely simple to use.
Why?
Even though the EFM32G is versatile, there
might be a need for specific external devices
such as extra RAM, FLASH, LCD. The EBI
simplifies the access to such devices.
How?
Through memory mapping the devices
appear as a part of the internal memory map.
When the processor performs read or writes
to the address range of the EBI, the EBI
handles the data transfers to and from the
external devices. The EBI may be interfaced
by the DMA, thus enabling operation in EM1.
Quick Facts
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