Freescale Semiconductor QorIQ LS1043A, Справочное руководство

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LS1043A
nRESET
K22 MCU
MSD
bootloader
CMSIS-DAP
application
UART1 Tx/Rx
JTAG signals
GPIO
UART Tx/Rx
GPIO
CMSIS-DAP
USB host
USB
Figure 5-2. CMSIS-DAP
CMSIS-DAP is managed by a Kinetis K22 MCU built on the ARM Cortex-M4 core. The
Kinetis K22 includes an integrated USB controller that can operate at clock rates of up to
120 MHz. The CMSIS-DAP circuit includes a status LED and a push button. The push
button asserts the reset signal to the target processor. The GPIO signals provide an
interface to a JTAG debug port on the target processor. In addition, signal connections
are available to implement a UART serial channel.
CMSIS-DAP features a mass storage device (MSD) bootloader, which provides a quick
and easy mechanism for loading different CMSIS-DAP applications, such as flash
programmers, run control debug interfaces, serial-to-USB converters, and so on.
5.3 GPIOs
The LS1043ARDB has no dedicated general purpose input/output (GPIO) pins. Instead,
GPIO functions are multiplexed internally on other signals, which must be disabled
before using the GPIO functions. GPIO is not needed for board operation. Most of the
GPIO pins are not available for external access because the pins are used for their
primary functions. Some GPIO pins are connected to a test point to allow access.
GPIO_4[6] to GPIO_4[9] can be used to drive four LED signals. The names of the GPIO
pins with and without test point access are shown in the table below.
Chapter 5 Debug and Input/Output
QorIQ LS1043A Reference Design Board Reference Manual, Rev. 0, 08/2015
Freescale Semiconductor, Inc. 49