LXT/HXT are external crystl oscillator and can be absent on custom board.
This enables configuring LXT/HXT presence:
1. By default, LXT/HXT are configured to be present, except M252 which has no HXT.
2. When LXT is configured to not present, lp_ticker/watchdog will clock by LIRC instead.
3. Limitations:
(1) On all targets, LIRC-clocked lp_ticker gets inaccurate and fails to pass tests.
(2) On NUC472/M453, HIRC-clocked PLL doesn't output 1MHz-aligned frequency. us_ticker gets slight inaccurate.
(3) On all targets, LIRC-clocked RTC is not supported due to no H/W path/RTC clock source reset to LXT on reset/RTC not trimmed for other clock rates.
4. On M263, TRNG's clock source defaults to LXT and needs special handling without LXT.
5. On M252, replace target.hxt-enable with target.hxt-present for consistency.
Workaround a bug where the boot stack size configuration option is not
passed on to armlink, the Arm Compiler's linker. Prefer
MBED_CONF_TARGET_BOOT_STACK_SIZE if present, as this is what the
configuration system should provide. Fall back to MBED_BOOT_STACK_SIZE
if MBED_CONF_TARGET_BOOT_STACK_SIZE is not defined, as in the case of
buggy tools. If both MBED_CONF_TARGET_BOOT_STACK_SIZE and
MBED_BOOT_STACK_SIZE are not defined, then we fall back to a hard-coded
value provided by the linkerscript. See
https://github.com/ARMmbed/mbed-os/issues/13474 for more information.
To allow overriding of the boot stack size from the Mbed configuration
system, consistently use MBED_CONF_TARGET_BOOT_STACK_SIZE rather than
MBED_BOOT_STACK_SIZE.
Fixes#10319
This caused a conflict. As CMSIS update introduced low level init, lets use the types
from CMSIS. We could potentionally use __cmsis_start but as I saw for some targets,
the init routine is slightly different. So rather keep what we have in targets, and just
use types already defined in CMSIS.
Add a "used" attribute to __vector_handlers to fix ARMC6 build with
the "-flto" flag.
(Error: L6236E: No section matches selector - no section to be FIRST/LAST. )
This attribute, attached to a function/variable, means that code must be emitted
for the function even if it appears that the function is not referenced.
On IAR, configure heap to 1KiB at a minimum and expandable, dependent on available SRAM. This requires IAR 8.x.
Support targets:
- NUMAKER_PFM_NUC472 w/ and w/o XRAM
- NUMAKER_PFM_M453
- NUMAKER_PFM_M487/NUMAKER_IOT_M487
- NUMAKER_IOT_M263A
- NUMAKER_M252KG
Chun-Chieh Li
cyliangtw
Martin Kojtal
Jaeden Amero
Maciej Bocianski