HAL Port — Implementation Details
This documentation explains how the eCos HAL specification has been mapped onto the M5282LITE hardware, and should be read in conjunction with that specification. The M5282LITE platform HAL package complements the M68K architectural HAL, the MCFxxxx variant HAL, and the MCF5282 processor HAL. It provides functionality which is specific to the target board.
Following a hard or soft reset the HAL will initialize or
reinitialize most of the on-chip peripherals. There is an exception
for RAM startup applications which depend on a ROM monitor for certain
services: the UARTs and the ethernet device will not be reinitialized
because they may be in use by RedBoot for communication with the host.
Full details of this initialization can be found in the function
For a ROM startup the HAL will perform additional initialization,
setting up the external DRAM and chip selects. Full details can be
found in the exported header
The platform HAL provides configuration options for the eCos system clock. This always uses the hardware timer PIT3, which should not be used directly by application code. The actual HAL macros for managing the clock are provided by the MCF5282 processor HAL. The specific numbers used are a characteristic of the platform because they depend on the processor speed. The gprof-based profiling code uses PIT2. Timers PIT0 and PIT1 are not used by eCos so application code is free to manipulate these as required.
The M5282LITE platform HAL does not affect the implementation of other parts of the eCos HAL specification. The MCF5282 processor HAL, the MCFxxxx variant HAL, and the M68K architectural HAL documentation should be consulted for further details.
The platform HAL package also provides a flash driver for the off-chip
ST M29W160EB flash chip or compatible. This driver is inactive by
default, and only becomes active if the configuration includes the
generic flash support
|2023-01-12||eCosPro Non-Commercial Public License|