Configuration — Platform-specific Configuration Options
The STM32X0G-EVAL board platform HAL package is loaded
automatically when eCos is configured for an
stm3241g target. 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 STM32X0G-EVAL board platform HAL package supports five separate startup types:
- This is the startup type which is normally used during application development. The board has RedBoot programmed into internal Flash at location 0x08000000 and uses external RAM at location 0x64000000. arm-eabi-gdb is then used to load a RAM startup application into memory from 0x64008000 and debug it. It is assumed that the hardware has already been initialized by RedBoot. By default the application will use the eCos virtual vectors mechanism to obtain services from RedBoot, including diagnostic output.
- This startup type can be used for finished applications which will be programmed into internal ROM at location 0x08000000. Data and BSS will be put into external RAM starting from 0x64000000. The application will be self-contained with no dependencies on services provided by other software. The program expects to boot from reset with ROM mapped at location zero. It will then transfer control to the 0x08000000 region. eCos startup code will perform all necessary hardware initialization.
- This startup type can be used for finished applications which will be programmed into internal ROM at location 0x08000000. Data and BSS will be put into internal SRAM starting from 0x20000284 (F2) or 0x20000288 (F4). Internal SRAM below this address is reserved for vector tables. The application will be self-contained with no dependencies on services provided by other software. The program expects to boot from reset with ROM mapped at location zero. It will then transfer control to the 0x08000000 region. eCos startup code will perform all necessary hardware initialization.
- This is the startup type 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 0x64000000 and entered at that address. eCos startup code will perform all necessary hardware initialization.
- This is a variation of the JTAG type that only uses internal memory. The application will be self-contained with no dependencies on services provided by other software. The program expects to be loaded from 0x20000284 (F2) or 0x20000288 (F4) and entered at that address. eCos startup code will perform all necessary hardware initialization.
RedBoot and Virtual Vectors
If the application is intended to act as a ROM monitor, providing
services for other applications, then the configuration option
CYGSEM_HAL_ROM_MONITOR should be set. Typically
this option is set only when building RedBoot.
If the application is supposed to make use of services provided by
a ROM monitor, via the eCos virtual vector mechanism, then the
should be set. By default this option is enabled when building for
a RAM startup, disabled otherwise. It can be manually disabled for
a RAM startup, making the application self-contained, as a testing
step before switching to ROM startup.
If the application does not rely on a ROM monitor for diagnostic services then the serial port will be claimed for HAL diagnostic output.
UART Serial Driver
The STM32X0G-EVAL board uses the STM32's internal UART serial support. The HAL diagnostic interface, used for both polled diagnostic output and RedBoot / GDB stub communication, is only expected to be available to be used on the UART 4 port (counting the first UART as UART1). This is because only UART 4 is actually routed to an external connector.
As well as the polled HAL diagnostic interface, there is also
CYGPKG_IO_SERIAL_CORTEXM_STM32 package which
contains all the code necessary to support interrupt-driven
operation with greater functionality. All six UARTs can be
supported by this driver Note: while it is possible for USART3 to
be configured to use this connector, the only advantage of USART3
would be flow control lines, which are not routed to the connector
on the STM32X0G board.
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 UART4 port (the same as the HAL diagnostic
interface), but the default configuration can be modified to
enable support for other serial ports. Note that in this package,
serial port numbering starts at 0, rather than 1. So for example,
to enable the serial driver for ports USART1 and USART2, enable
the configuration options "ST STM32 serial port 0 driver"
"ST STM32 serial port 1 driver"
The STM32X0G-EVAL board is fitted with an Ethernet port connected
via a DP83847 PHY to the STM32's on-chip Ethernet MAC. This is supported
in eCosPro with a driver for the lwIP networking stack,
contained in the package
At the present time it only supports the lwIP networking stack, and cannot
be used for either the BSD networking stack, nor RedBoot.
The driver will be inactive (not built and greyed out in the eCos
Configuration Tool) unless the platform HAL option "STM32
is enabled. This option in turn is only active if the "Common
Ethernet support" (
package is included in your configuration. As the STM32 ethernet
driver is an lwIP-only driver, it is most appropriate to choose
lwip_eth template as a starting point when
choosing an eCos configuration, which will cause the necessary
packages to be automatically included.
The platform HAL defines a further configuration option "Use MCO as
indicates whether the MCO1 clock signal is used as the 25MHz clock for the
Ethernet PHY. With this option disabled, the on-board 25MHz crystal
oscillator located at X1 can be used instead, although in that case the
board jumper J5 must be changed. You may wish to make this change if
you wish to use the MCO1 clock output for another purpose. Consult the
STM32 clock and ethernet documentation for more details.
An SPI bus driver is available for the STM32 in the package
"ST STM32 SPI driver" (
The only SPI device instantiated by default is for an external
Aardvark SPI test board, connected to SPI bus 2 with pin PI0
selected as the chip select. To disable the Aardvark device
support, the platform HAL contains an option "SPI devices"
can be disabled. No other SPI devices are instantiated.
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 STM32 SPI device driver.
The STM32 variant HAL provides the main I²C hardware driver itself,
CYGPKG_HAL_STM32_I2C. But the platform
I²C support can also be configured separately at
CYGPKG_HAL_CORTEXM_STM32_STM32X0G_EVAL_I2C. This ensures
that the M24C64 serial EEPROM is instantiated and becomes available for
<cyg/io/i2c.h>, and also
ensures the STM32's I²C bus 1 is enabled for it. This option also
allows the m24c64.c test is built. In order to allow writes to the serial
EEPROM, you must ensure that the STM32X0G-EVAL jumper JP24 is fitted.
The m24c64.c test will not pass otherwise.
The STM32 processor variant HAL provides an ADC driver. The STM32X0G-EVAL platform HAL enables the support for the devices ADC1, ADC2 and ADC3 and for configuration of the respective ADC device input channels.
Consult the generic ADC driver API documentation in the eCosPro Reference Manual for further details on ADC support in eCosPro, along with the configuration options in the STM32 ADC device driver.
The STM32 has a dual BXCAN device for CAN support. This consists of a master device, BXCAN1, and a slave device, BXCAN2. If BXCAN2 is to be used, BXCAN1 must be powered and clocked, regardless of whether it is to be used for CAN traffic. BXCAN1 shares IO pins with the FSMC, which controls the external SRAM. Therefore, BXCAN1 can only be used in ROMINT startup mode.
The board has a single external CAN socket, to which either BXCAN1 or BXCAN2 can be routed, based on the settings of JP3 and JP10. By default these jumpers are set to route neither CAN device to the socket, and jumpers must be fitted to route the desired CAN device as appropriate. See the board reference manual for details.
Consult the generic CAN driver API documentation in the eCosPro Reference Manual for further details on CAN support in eCosPro, along with the documentation and configuration options in the BXCAN device driver.
The STM32's on-chip Flash may be programmed and managed using the
Flash driver located in the "STM32 Flash memory support"
CYGPKG_DEVS_FLASH_STM32) 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 STM32 variant present on the
A number of aspects of Flash driver behaviour can be configured within that driver, such as program/erase parallelism and program burst size. Consult the driver for more details.
|2021-09-02||eCosPro Non-Commercial Public License|