Target — ZX Spectrum Next (+zxn)

Config	lib/config/zxn.cfg
Trees	libsrc/target/zxn/, libsrc/newlib/target/zxn/, examples/zxn/
Headers	include/arch/zxn.h (nextreg, copper, MMU, …)
Wiki	wiki/platforms/Platform---ZX-Spectrum-Next-zxn.md
CPU skill	cpu-z80n (Next opcodes, nextreg, copper)
Help	zcc +zxn -h

Not 48/128 (+zx)

Bare +zxn is Next. Do not use zx_clib, +zx subtypes, or Spectrum-only recipes.

Defaults (critical)

Option	Default in zxn.cfg
CPU	-mz80n
CLIB	sdcc_iy (newlib + reserve IY)
SUBTYPE	default → appmake +zxn
Defines	__ZXNEXT, __Z80N, …

So bare zcc +zxn … is newlib, not classic.

CLIB map

CLIB	World	Notes
classic	classic	name is classic, not default; -lzxn_clib -lndos; z80n_crt0
new	newlib	sccz80
sdcc_ix / sdcc_iy	newlib	both use lib/clibs/sdcc_ix products; IY reserved on sdcc_iy

Subtypes

Subtype	Role
default / zxn / tap	Next packaging (+zxn)
bin	--bin
sna / snx	snapshots
nex	.nex for NextOS / emulators
dot / dotx	esxDOS DOT
dot-n / dotx-n / dotn / dotn-n	DOT/DOTN + NextOS defines

Classic disk often needs -lesxdos (default classic still has ndos stubs).

Recipes

zcc +zxn -vn hi.c -o hi -create-app                    # newlib sdcc_iy
zcc +zxn -clib=classic -subtype=nex -create-app …
zcc +zxn -clib=new -subtype=nex -create-app …
zcc +zxn -subtype=dot -create-app …

Hardware-facing code

Need	Where
Next opcodes (mul de, nextreg, …)	cpu-z80n, assemble -mz80n
NextReg / MMU / copper symbols	include/arch/zxn.h, config_zxn.h
Copper program model	cpu-z80n § Copper + https://wiki.specnext.dev/Copper

Agent notes

1. Always -mz80n for Next-only opcodes (already in OPTIONS).
2. Float A/B on Next: math32_z80n when measuring HW mul.
3. Related: cpu-z80n, library-newlib, tool-appmake.