This moves the following modules to a architecture-specific Makefile.dep
file:
- cortexm_common
- cortexm_common_periph
- newlib
- newlib_nano
- periph
The internal DC/DC converter is more efficient compared to the LDO
regulator. The downside of the DC/DC converter is that it requires an
external inductor to be present on the board. Enabling the DC/DC
converter is guarded with NRF5X_ENABLE_DCDC, this macro must be defined
if the DC/DC converter is to be enabled.
bitarithm.h is not needed for the interface of shed but may cause conflicts
due to different definitions of SETBIT and CLRBIT
common implementations are: (value, offset) xor (value, mask) bitarithm
implements the later
frac.c and nrf52/usbdev.c use bitarithm.h but where missing the include
sam0/rtt.c defined a bit using mask from bitarithm,
changed that to the soulution used in sam0/rtc.c
- Removed stdio_init() from newlib's _init(), as this is too late in the boot
process to allow DEBUG()ing during periph_init()
- Added stdio_init() to the various cpu_init() routines of the ARM CPUs just
before periph_init()
Engineering sample A doesn't have a functional USB peripheral (errata
issue 94). This commit adds an assertion check for this revision to
prevent some developer headaches.
The timer_clear function doesn't clear the hardware timer counter, but
is designed to clear the allocation of the channel. The consequence is
that the IFS timer here is not set to zero in the callback, but only
stopped at the current value. When the timer is started again, it has to
count the full timer range until it matches the timeout value again.
This commit fixes this issue by using timer_set instead of
timer_set_absolute. This way the current timer value (when the timer is
stopped) is read and the IFS timeout value is added to the current timer
value.
ieee802.15.4 specifies 40 symbols as LIFS value and 12 symbols as SIFS
value. Furthermore, the 2.4Ghz DSSS mode has a symbol rate of
62.5Ksymbols/s. To have the LIFS and SIFS in the code match the timings
from the specification, the TIMER_FREQ must match the symbol rate of
62.5Ksymbol/s such that one tick of the timer equals one symbol in time.
