Configuration — Platform-specific Configuration Options


The MIMXRT1050-EVK board platform HAL package is loaded automatically when eCos is configured for a suitable target, e.g. mimxrt1050_evk. It should never be necessary to load this package explicitly. Unloading the package should only happen as a side effect of switching target hardware.


The MIMXRT1050-EVK board platform HAL package supports three separate startup types:

This is the default startup type. It is used to build applications that are loaded via a JTAG interface. The application will be self-contained with no dependencies on services provided by other software. The program expects to be loaded from 0x20209000 and entered at 0x20209008. eCos startup code will perform all necessary hardware initialization.

This startup type is currently essentially equivalent to the JTAG startup type in memory layout and usage. This startup is intended to be used for RedBoot when it is loaded from an external memory device such as an SD card or FlexSPI flash.

The program expects to be loaded from 0x20209020, and the eCos startup code will perform all necessary hardware initialisation. The difference in load address from the JTAG startup is to allow space for the boot ROM configuration structures required when the application is packaged into a boot image.

This startup type is for applications that are loaded via RedBoot into external SDRAM. They rely on services supplied by RedBoot. RAM applications can only be loaded via RedBoot since the SDRAM is only initialized when RedBoot is loaded from an external boot memory.

UART Serial Driver

The MIMXRT1050-EVK board uses the RT10XX internal UART serial support. The HAL diagnostic interface, used for both polled diagnostic output and GDB stub communication, is only expected to be available to be used on the LPUART1 port.

As well as the polled HAL diagnostic interface, there is also a CYGPKG_IO_SERIAL_NXP_LPUART package which contains all the code necessary to support interrupt-driven operation with greater functionality.

It is not recommended to use the interrupt-driven serial driver with a port at the same time as using that port for HAL diagnostic I/O.

This driver is not active until the CYGPKG_IO_SERIAL_DEVICES configuration option within the generic serial driver support package CYGPKG_IO_SERIAL is enabled in the configuration. By default this will only enable support in the driver for the LPUART1 port (the same as the HAL diagnostic interface), but the default configuration can be modified to enable support for other serial ports.

SPI Driver

An SPI bus driver is available in the package "NXP LPSPI Support" (CYGPKG_DEVS_SPI_NXP_LPSPI).

Consult the generic SPI driver API documentation in the eCosPro Reference Manual for further details on SPI support in eCosPro, along with the configuration options in the NXP SPI device driver.

I²C Driver

Support for NXP I²C busses is provided by the "NXP LPI2C Support" package (CYGPKG_DEVS_I2C_NXP_LPI2C). The variant HAL causes two buses to be instantiated. These have been tested using external I²C devices.

Flash Driver

The external FlexSPI Flash may be programmed and managed using the Flash driver located in the "NXP FlexSPI Support" (CYGPKG_DEVS_FLASH_NXP_FLEXSPI) package. This driver is enabled automatically if the generic "Flash device drivers" (CYGPKG_IO_FLASH) package is included in the eCos configuration. The driver will configure itself automatically for the size and parameters of the specific flash variant present on the MIMXRT1050-EVK board.

Watchdog Driver

The board uses the RT10XX Watchdog timer 1. The CYGPKG_DEVICES_WATCHDOG_ARM_IMX package contains all the code necessary to support this device. Within that package the CYGNUM_DEVS_WATCHDOG_ARM_IMX_DESIRED_TIMEOUT_MS configuration option controls the watchdog timeout, and by default will force a reset of the board upon timeout. This driver is not active until the generic watchdog device support package, CYGPKG_IO_WATCHDOG, is included in the configuration.

PWM Driver

Support for the NXP FlexPWM devices is provided by the "NXP PWM Support" package (CYGPKG_DEVS_PWM_NXP) which needs to be used in conjunction with the CYGPKG_IO_PWM generic PWM package. Refer to the documentation for that package for usage details.

The RT10XX contains four FlexPWM devices, each of which contains four independent submodules. Each submodule has two semi-independent output lines that can be routed to a variety of pads. Each submodule is presented as a separate PWM device and have names such as "pwm1.0" for FlexPWM 1 submodule 0 or "pwm3.2" for FlexPWM 3 submodule 2. The output lines are mapped on to channel 0 for output A and channel 1 for output B. These outputs are semi-independent in that they must share a period, but may have different duty cycles.