[wrt3200acm] openwrt 19.07 minimal

Hi,
I want a minimal setup, what packages do I need to install to have everything ok?
Thanks.

Just select the device, no need to add packages. The device specs define all necessary packages.
(But if you want LuCI GUI, also select it.)

I try and with command "./scripts/diffconfig.sh > ciccio"
i have only

CONFIG_TARGET_mvebu=y
CONFIG_TARGET_mvebu_cortexa9=y
CONFIG_TARGET_mvebu_cortexa9_DEVICE_linksys_wrt3200acm=y

other is all comment

Easiest might be to just start with empty .config and use "make menuconfig".

Or if you continue with your current style, use "make defconfig" to expand your minimal .config to a fully populated one.

Yes, bat I find it strange that there are no specific modules, example for mwlwifi

Other packages should be pulled in by dependencies, once you select the device in menuconfig.

I tried but I'm not there.
if I do ./scripts/diffconfig.sh> ciccio
I only have this:
CONFIG_TARGET_mvebu=y
CONFIG_TARGET_mvebu_cortexa9=y
CONFIG_TARGET_mvebu_cortexa9_DEVICE_linksys_wrt3200acm=y

grep mwlwifi .config

should show that the dependency has been honoured, for example.

:hushed:
$ grep mwlwifi .config
CONFIG_DEFAULT_kmod-mwlwifi=y
CONFIG_DEFAULT_mwlwifi-firmware-88w8964=y
CONFIG_PACKAGE_mwlwifi-firmware-88w8864=m
CONFIG_PACKAGE_mwlwifi-firmware-88w8897=m
CONFIG_PACKAGE_mwlwifi-firmware-88w8964=y
CONFIG_PACKAGE_mwlwifi-firmware-88w8997=m
CONFIG_PACKAGE_kmod-mwlwifi=y

but why ./scripts/diffconfig.sh> ciccio
does not put the differences of the modules?

Because you have not explicitly changed / selected anything from the default.