Actually really working

Ok, both sides work as expected, need to write a keymap.

app/boards/shields/Kconfig.defconfig

@@ -0,0 +1,14 @@
+
+
+
+config ZMK_KEYBOARD_NAME
+	default "cradios"
+
+# Unable to use interrupts as the same pin number is used
+# across A & B controllers, and STM32F303CCT6 can't enable
+# interrutps for multiple controllers for the same "line"
+# for the external interrupts.
+config ZMK_KSCAN_GPIO_POLLING
+	default y
+
+

app/boards/shields/Kconfig.shield

@@ -0,0 +1,5 @@
+# Copyright (c) 2020 Pete Johanson
+# SPDX-License-Identifier: MIT
+
+config SHIELD_CRADIOS
+	def_bool $(shields_list_contains,cradios)

app/boards/shields/cradios.dtsi

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2020 Pete Johanson
+ *
+ * SPDX-License-Identifier: MIT
+ */
+ #include <dt-bindings/zmk/matrix-transform.h>
+ 
+/ {
+	chosen {
+		zmk,kscan = &kscan0;
+		zmk,matrix_transform = &default_transform;
+	};
+		
+	default_transform: keymap_transform_0 {
+	compatible = "zmk,matrix-transform";
+        columns = <34>;
+        rows = <1>;
+		map = <
+RC(0,0) RC(0,1) RC(0,2) RC(0,3) RC(0,4) 		RC(0,21) RC(0,20) RC(0,19) RC(0,18) RC(0,17) 
+RC(0,5) RC(0,6) RC(0,7) RC(0,8) RC(0,9) 		RC(0,26) RC(0,25) RC(0,24) RC(0,23) RC(0,22)   
+RC(0,10)RC(0,11) RC(0,12) RC(0,13) RC(0,14) 		RC(0,31) RC(0,30) RC(0,29) RC(0,28) RC(0,27) 
+RC(0,15)  RC(0,16) 					RC(0,33) RC(0,32)  
+>;
+
+
+	};	
+	
+	kscan0: kscan {
+		compatible = "zmk,kscan-gpio-direct";
+		label = "KSCAN";
+	};
+	
+	
+	
+	
+	bt_unpair_combo: bt_unpair_combo {
+		compatible = "zmk,bt-unpair-combo";
+	};
+	
+	
+	
+		};
+		
+		
+		&kscan0 {
+		input-gpios
+		= <&pro_micro_d 7 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_a 0 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_a 1 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_a 2 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_a 3 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 15 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 14 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 16 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 10 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 1 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 2 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 3 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_a 6 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 5 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 6 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 8 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			, <&pro_micro_d 9 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>
+			;
+};
+	
+	

app/boards/shields/cradios.keymap

@@ -0,0 +1,18 @@
+#include <behaviors.dtsi>
+#include <dt-bindings/zmk/keys.h>
+
+
+/ {
+        keymap {
+                compatible = "zmk,keymap";
+
+                default_layer {
+		bindings = <
+		&kp Q &kp W &kp E &kp R &kp T 		&kp Y &kp U  &kp I    &kp O   &kp P 
+		&kp A &kp S &kp D &kp F &kp G 		&kp H &kp J  &kp K    &kp L   &kp SCLN 
+		&kp Z &kp X &kp C &kp V &kp B		&kp N &kp M  &kp CMMA &kp DOT &kp FSLH
+			      &kp NUM_1 &kp NUM_2 		&kp NUM_3 &kp NUM_4 
+			      >;
+		};
+	};
+};

app/boards/shields/cradios_left.conf

@@ -0,0 +1,2 @@
+CONFIG_ZMK_SPLIT=y
+CONFIG_ZMK_SPLIT_BLE_ROLE_CENTRAL=y

app/boards/shields/cradios_left.overlay

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2020 Pete Johanson
+ *
+ * SPDX-License-Identifier: MIT
+ */
+#include "cradios.dtsi"
+
+
+
+
+
+
+&bt_unpair_combo {
+	key-positions = <0 16>;
+};

app/boards/shields/cradios_right.conf

@@ -0,0 +1,2 @@
+CONFIG_ZMK_SPLIT=y
+CONFIG_ZMK_SPLIT_BLE_ROLE_PERIPHERAL=y

app/boards/shields/cradios_right.overlay

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2020 Pete Johanson
+ *
+ * SPDX-License-Identifier: MIT
+ */
+#include "cradios.dtsi"
+
+&default_transform {
+	col-offset = <17>;
+};
+
+
+
+
+&bt_unpair_combo {
+	key-positions = <21 32>;
+};