provides a device driver for the wallclock device in the ST M41TXX
Serial Real-Time Clock chips. This is a real-time clock, alarm and
watchdog in a single package. eCos only currently supports the
real-time clock function.
The package will usually be loaded into the configuration automatically whenever selecting a target which contains a compatible chip. By default it will provide the standard eCos wallclock device, although another implementation such as software emulation may be selected if desired. The only other configuration options related to this package allow users to change the compiler flags. If the application does not actually use the wallclock device, directly or indirectly, then the code should get removed automatically at link-time to ensure that the application does not suffer any unnecessary overheads.
This wallclock device driver package implements the standard
functionality required by the generic wallclock support
CYGPKG_IO_WALLCLOCK. The functionality is not
normally accessed directly. Instead it is used by the C library time
package to implement standard calls such as
gmtime. The eCos C library also provides a
changing the current wallclock setting. In addition RedBoot provides
a date command which interacts with the wallclock
M41TXX platform support is implemented via the generic I2C API, as
defined by the package
CYGPKG_IO_I2C. The platform
HAL can just provide a
cyg_i2c_wallclock_m41txx. The M41TXX
driver will now use I2C rx and tx operations to interact with the
In addition the M41TXX device driver package
CYGPKG_DEVICES_WALLCLOCK_ST_M41TXX should be
included in the CDL target entry so that it gets loaded automatically
whenever eCos is configured for that target.