nuttx/arch
raiden00pl a8ac2e74e0 arch/nrf52: add SAADC external TIMER trigger over PPI
The SAADC internal sample timer only works with a single enabled
channel, so hardware-timed multi-channel scan was not possible.  Add
NRF52_SAADC_TIMER_PPI, a third trigger mode in which a general-purpose
TIMER compare event is routed to TASKS_SAMPLE over PPI.  All enabled
channels are scanned, and the TIMER prescaler allows much lower sample
rates than the internal timer, which is limited to 16MHz/CC with CC in
80..2047.

NRF52_SAADC_CONTINUOUS is no longer tied to the internal timer and
works with either source.  Its EasyDMA buffers now hold
NRF52_SAADC_CONTINUOUS_BUFLEN whole scans rather than that many single
samples, so MAXCNT becomes chan_len * BUFLEN.  Samples are interleaved
scan by scan, so a channel map is built once at configure() time and
passed to the upper half with the batch; the upper half already accepts
a per-sample channel array.  A single-channel configuration produces
the same MAXCNT and the same delivery as before.

Because both features want a PPI channel, add a build-time check that
NRF52_SAADC_PPI_CHANNEL and NRF52_SAADC_CONTINUOUS_PPI_CH differ, and
constrain the latter under the SoftDevice controller like the former.

NRF52_SAADC_CHANNELS gains a default and range for the new mode, and
documents that the internal timer is restricted to one channel.

Assisted-by: Claude Code
Signed-off-by: raiden00pl <raiden00@railab.me>
2026-09-28 11:20:31 +02:00
..
arm arch/nrf52: add SAADC external TIMER trigger over PPI 2026-09-28 11:20:31 +02:00
arm64 arch/arm64/imx9: add an ELE-backed /dev/random driver. 2026-09-27 11:02:13 -03:00
avr arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
ceva arch/atomic: remove up_testset in spinlock 2026-09-08 08:58:54 +08:00
dummy
hc tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
mips arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
misoc arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
or1k arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
renesas nuttx/libc: refine the atomic related Kconfig 2026-08-24 13:20:45 +08:00
risc-v arch/risc-v/eic7700x: Describe the pads through procfs. 2026-09-28 16:19:01 +08:00
sim arch/sim: buffer several mouse reports 2026-09-25 10:36:28 +02:00
sparc arch/atomic: remove up_testset in spinlock 2026-09-08 08:58:54 +08:00
tricore arch/atomic: remove up_testset in spinlock 2026-09-08 08:58:54 +08:00
x86 arch/x86: Add -P to CPP to suppress linemarkers. 2026-09-17 16:21:59 +08:00
x86_64 arch/x86_64: Implement up_addrenv_fork() and provide POSIX fork(). 2026-09-24 18:02:36 -03:00
xtensa arch/xtensa: Provide POSIX fork() on the ESP32-S3. 2026-09-26 11:13:57 -03:00
z16 tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
z80 style: fix checkpatch issues after debug.h move 2026-04-07 07:50:06 -03:00
CMakeLists.txt cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
Kconfig arch/xtensa: Provide POSIX fork() on the ESP32-S3. 2026-09-26 11:13:57 -03:00