Table 4. i.MX28 Digital and Analog Modules (continued)
Block
Mnemonic
HSADC
I2C(2)
ICOLL
L2 Switch
LCDIF
LRADC
OCOTP
Controller
PINCTRL
Block Name Subsystem
Brief Description
High-speed Connectivity
ADC
peripherals
I2C module
Connectivity
peripherals
The high-speed ADC block is designed to sample an analog input with 12-bit
resolution and a sample rate of up to 2 Msps. The output of the HSADC block
can be moved to the external memory through APBH-DMA. A typical user
case of the HSADC is to work with the PWM block to drive an external linear
image scanner sensor.
The I2C is a standard two-wire serial interface used to connect the chip with
peripherals or host controllers. The I2C operates up to 400 kbps in either I2C
master or I2C slave mode. Each I2C has a dedicated DMA channel and can
also controlled by CPU in PIO or PIO queue modes. It supports both 7-bit and
10-bit device address in master mode, and has programmable 7-bit address
in slave mode.
Interrupt
Collector
System control The ARM9 CPU core has two interrupt input lines, IRQ and FIQ. The interrupt
collector (ICOLL) can steer any of 128 interrupt sources to either the FIQ or
IRQ line of the ARM9 CPU.
3-Port L2
Switch
Network Control Programmable 3-Port Ethernet Switch with QOS
LCD Interface Multimedia
peripherals
The LCDIF provides display data for external LCD panels from simple
text-only displays to WVGA, 16/18/24 bpp color TFT panels. The LCDIF
supports all of these different interfaces by providing fully programmable
functionality and sharing register space, FIFOs, and ALU resources at the
same time. The LCDIF supports RGB (DOTCLK) modes as well as system
mode including both VSYNC and WSYNC modes.
Low resolution Connectivity
ADC module peripherals
The sixteen-channel 12-bit low-resolution ADC (LRADC) block is used for
voltage measurement. Channels 0 – 6 measure the voltage on the seven
application-dependent LRADC pins. The auxiliary channels can be used for
a variety of uses, including a resistor-divider-based wired remote control,
external temperature sensing, touch-screen, and other measurement
functions.
On-chip OTP Security
controller
The on-chip one-time-programmable (OCOTP) ROM serves the functions of
hardware and software capability bits, Freescale operations and unique-ID,
the customer-programmable cryptography key, and storage of various ROM
configuration bits.
Pin control
and GPIO
System control Used for general purpose input/output to external ICs. Each GPIO bank
peripherals
supports 32 bits of I/O.
i.MX28 Applications Processors Data Sheet for Consumer Products, Rev. 1
8
Freescale Semiconductor