Can I get QMK to access 4 layers by holding (MO?) 0-2 keys? If so, what’s best practice for this? I’ve got a wicked hitchhiker’s thumb and I want to use it!
base(up,up)
layer2(down,up)
layer3(up,down)
layer4(down,down)
Pretty much all Plancks do that (lower, raise, adjust), so I would look at, say, keyboards/planck/keymaps/pok3r to see how it’s done.
Edit: actually that is a bad example, they do it in a roundabout way. What you want is simply to put MO(1) and MO(2) on the first layer, and then on layers 1 and 2 replace them with MO(3). That’s it.
You can even add one more layer, depending on the order in which those keys are pressed…
3 Likes
I was actually just about to post NOT to do it how the Planck does it, haha.
I’m actually not using the exact layer setup you mentioned, but I have a TG (toggle) layer that also has a layer key on it (via fall thru to the lower layer).
@wavebeem’s solution does not really address the question, but does show how to use MO.
@deshipu’s solution with stacked MO doesn’t work either. It seems to cause an undefined combination of all 3 layers, unless I am doing it wrong. I attached a QMK Configurator keymap file with an attempt at it (exactly as the OP asked it).
I am going to look into how Planks do it, but if someone knows how to do this in a simpler way, please let me know! Thanks 
EDIT: I was getting confused cause numpad wasn’t enabled while trying to use my fourth layer (MO(3)). Regardless, this keymap is here as an example for others.
Keymap:
{
"version": 1,
"notes": "",
"documentation": "\"This file is a QMK Configurator export. You can import this at <https://config.qmk.fm>. It can also be used directly with QMK's source code.\n\nTo setup your QMK environment check out the tutorial: <https://docs.qmk.fm/#/newbs>\n\nYou can convert this file to a keymap.c using this command: `qmk json2c {keymap}`\n\nYou can compile this keymap using this command: `qmk compile {keymap}`\"\n",
"keyboard": "ferris/sweep",
"keymap": "cusp_hold_layout",
"layout": "LAYOUT_split_3x5_2",
"layers": [
[
"KC_Q",
"KC_W",
"KC_E",
"KC_R",
"KC_T",
"KC_Y",
"KC_U",
"KC_I",
"KC_O",
"KC_P",
"KC_A",
"KC_S",
"KC_D",
"KC_F",
"KC_G",
"KC_H",
"KC_J",
"KC_K",
"KC_L",
"KC_SCLN",
"KC_Z",
"KC_X",
"KC_C",
"KC_V",
"KC_B",
"KC_N",
"KC_M",
"KC_COMM",
"KC_DOT",
"KC_SLSH",
"MO(1)",
"KC_SPC",
"OSM(MOD_LSFT)",
"MO(2)"
],
[
"KC_ESC",
"KC_PSCR",
"KC_VOLD",
"KC_VOLU",
"KC_ESC",
"KC_HOME",
"KC_PGDN",
"KC_PGUP",
"KC_END",
"KC_NO",
"OSM(MOD_LGUI)",
"OSM(MOD_LALT)",
"OSM(MOD_LSFT)",
"OSM(MOD_LCTL)",
"KC_NO",
"KC_LEFT",
"KC_DOWN",
"KC_UP",
"KC_RGHT",
"KC_BSPC",
"KC_NO",
"KC_NO",
"KC_APP",
"KC_TAB",
"KC_NO",
"KC_NO",
"KC_ENT",
"KC_NO",
"KC_NO",
"KC_DEL",
"KC_NO",
"KC_NO",
"KC_NO",
"MO(3)"
],
[
"KC_EXLM",
"KC_AT",
"KC_HASH",
"KC_DLR",
"KC_PERC",
"KC_CIRC",
"KC_AMPR",
"KC_ASTR",
"KC_EQL",
"KC_COLN",
"KC_GRV",
"KC_TILD",
"KC_LCBR",
"KC_LPRN",
"KC_LBRC",
"KC_UNDS",
"OSM(MOD_RCTL)",
"OSM(MOD_RSFT)",
"OSM(MOD_RALT)",
"OSM(MOD_RGUI)",
"KC_LT",
"KC_GT",
"KC_RCBR",
"KC_RPRN",
"KC_RBRC",
"KC_BSLS",
"KC_MINS",
"KC_PLUS",
"KC_SLSH",
"KC_QUES",
"MO(3)",
"KC_NO",
"KC_NO",
"KC_NO"
],
[
"TO(4)",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_PAST",
"KC_PMNS",
"KC_P7",
"KC_P8",
"KC_P9",
"KC_PPLS",
"OSM(MOD_LGUI)",
"OSM(MOD_LALT)",
"OSM(MOD_LSFT)",
"OSM(MOD_LCTL)",
"KC_PSLS",
"KC_P0",
"KC_P4",
"KC_P5",
"KC_P6",
"KC_PEQL",
"QK_BOOT",
"DB_TOGG",
"KC_NO",
"KC_NO",
"KC_NUM",
"KC_PDOT",
"KC_P1",
"KC_P2",
"KC_P3",
"KC_PENT",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO"
],
[
"KC_TRNS",
"KC_W",
"KC_E",
"KC_R",
"KC_T",
"KC_Y",
"KC_U",
"KC_I",
"KC_O",
"KC_P",
"KC_A",
"KC_S",
"KC_D",
"KC_F",
"KC_G",
"KC_H",
"KC_J",
"KC_K",
"KC_L",
"KC_P",
"KC_Z",
"KC_X",
"KC_C",
"KC_V",
"KC_B",
"KC_N",
"KC_M",
"KC_COMM",
"KC_DOT",
"KC_SCLN",
"KC_LSFT",
"KC_SPC",
"OSM(MOD_RSFT)",
"MO(5)"
],
[
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"KC_NO",
"TO(0)",
"KC_NO"
]
],
"author": ""
}