Arm 15.3.1 and Pico SDK a1438dff1d38bd9c65dbd693f0e5db4b9ae91779 ready.
PICO_SDK_PATH is ~/Developer/Projects/NeXTsound/.tools/pico-sdk
Target board (PICO_BOARD) is 'waveshare_rp2350_zero'.
Using board configuration from ~/Developer/Projects/NeXTsound/.tools/pico-sdk/src/boards/include/boards/waveshare_rp2350_zero.h
Pico Platform (PICO_PLATFORM) is 'rp2350-arm-s'.
Build type is Release
Forcing fetch of picotool from git
Downloading Picotool
Using picotool from ~/Developer/Projects/NeXTsound/.tools/picotool/picotool/picotool
TinyUSB available at ~/Developer/Projects/NeXTsound/.tools/pico-sdk/lib/tinyusb/hw/bsp/rp2040; enabling build support for USB.
-- Configuring done (0.3s)
-- Generating done (0.0s)
-- Build files have been written to: ~/Developer/Projects/NeXTsound/.build/firmware
[1/5] cd ~/Developer/Projects/NeXTsound/.build/firmware/pico-sdk/src/rp2350/boot_stage2 && /opt/homebrew/bin/cmake -E touch_nocreate ~/Developer/Projects/NeXTsound/Firmware/CMakeLists.txt
[2/5] Performing build step for 'picotoolBuild'
[1/3] Performing build step for 'enc_bootloader'
ninja: no work to do.
[2/3] No install step for 'enc_bootloader'
[3/3] Completed 'enc_bootloader'
[3/5] Performing install step for 'picotoolBuild'
[1/4] Performing build step for 'enc_bootloader'
ninja: no work to do.
[2/4] No install step for 'enc_bootloader'
[3/4] Completed 'enc_bootloader'
[3/4] Install the project...
-- Install configuration: "Release"
[4/5] Performing test step for 'picotoolBuild'
picotool v2.3.1 (Darwin, AppleClang-21.0.0.21000334, Release)

This version of picotool was compiled without USB support. Some commands are not available.
[5/5] Completed 'picotoolBuild'
SRAM-only ELF: 2 load segments; entry 0x20000178
SRAM guard rejects the flash-linked negative control.
   text	   data	    bss	    dec	    hex	filename
  60856	      0	  18316	  79172	  13544	~/Developer/Projects/NeXTsound/.build/firmware/nxs_firmware.elf
File ~/Developer/Projects/NeXTsound/.build/firmware/nxs_firmware.uf2 family ID 'rp2350-arm-s':

Program Information
 name:                NeXTsound development firmware
 version:             1ddf2de9-dirty
 description:         USB audio and HID control mono I2S muted start
 binary start:        0x10000000
 binary end:          0x1000d5b8
 target chip:         RP2350
 image type:          ARM Secure

Fixed Pin Information
 none

Build Information
 sdk version:         2.2.0
 pico_board:          waveshare_rp2350_zero
 boot2_name:          boot2_w25q080
 build date:          Oct 18 2026
 build attributes:    Release

Metadata Block 1
 address:             0x10000138
 next block address:  0x1000d5a4
 block type:          image def
 target chip:         RP2350
 image type:          ARM Secure
 extra security:      not enabled

Metadata Block 2
 address:             0x1000d5a4
 next block address:  0x10000138
 block type:          ignored