Add TX Bolt protocol support for Stenography

Requires virtser; Allows QMK to speak the TX BOlt protocol used by stenography machines and software (such as Plover). The upside is that Plover can be configured to listen only to TX Bolt allow the keyboard to switch layers without need to enable/disable the Plover software, or to have a second non-Steno keyboard work concurrently.

2 files changed, 94 insertions, 0 deletions

diff --git a/quantum/process_keycode/process_steno.c b/quantum/process_keycode/process_steno.c
new file mode 100644
index 0000000000..211f00a5a2
--- /dev/null
+++ b/quantum/process_keycode/process_steno.c
@@ -0,0 +1,82 @@
+#include "process_steno.h"
+#include "quantum_keycodes.h"
+#include "keymap_steno.h"
+#include "virtser.h"
+
+uint8_t state[4] = {0};
+uint8_t pressed = 0;
+
+
+// TxBolt Codes
+#define TXB_NUL 0
+#define TXB_S_L 0b00000001
+#define TXB_T_L 0b00000010
+#define TXB_K_L 0b00000100
+#define TXB_P_L 0b00001000
+#define TXB_W_L 0b00010000
+#define TXB_H_L 0b00100000
+#define TXB_R_L 0b01000001
+#define TXB_A_L 0b01000010
+#define TXB_O_L 0b01000100
+#define TXB_STR 0b01001000
+#define TXB_E_R 0b01010000
+#define TXB_U_R 0b01100000
+#define TXB_F_R 0b10000001
+#define TXB_R_R 0b10000010
+#define TXB_P_R 0b10000100
+#define TXB_B_R 0b10001000
+#define TXB_L_R 0b10010000
+#define TXB_G_R 0b10100000
+#define TXB_T_R 0b11000001
+#define TXB_S_R 0b11000010
+#define TXB_D_R 0b11000100
+#define TXB_Z_R 0b11001000
+#define TXB_NUM 0b11010000
+
+#define TXB_GRP0 0b00000000
+#define TXB_GRP1 0b01000000
+#define TXB_GRP2 0b10000000
+#define TXB_GRP3 0b11000000
+#define TXB_GRPMASK 0b11000000
+
+#define TXB_GET_GROUP(code) ((code & TXB_GRPMASK) >> 6)
+
+uint8_t boltmap[64] = {
+  TXB_NUL, TXB_NUM, TXB_NUM, TXB_NUM, TXB_NUM, TXB_NUM, TXB_NUM,
+  TXB_S_L, TXB_S_L, TXB_T_L, TXB_K_L, TXB_P_L, TXB_W_L, TXB_H_L,
+  TXB_R_L, TXB_A_L, TXB_O_L, TXB_STR, TXB_STR, TXB_NUL, TXB_NUL,
+  TXB_NUL, TXB_STR, TXB_STR, TXB_E_R, TXB_U_R, TXB_F_R, TXB_R_R,
+  TXB_P_R, TXB_B_R, TXB_L_R, TXB_G_R, TXB_T_R, TXB_S_R, TXB_D_R,
+  TXB_NUM, TXB_NUM, TXB_NUM, TXB_NUM, TXB_NUM, TXB_NUM, TXB_Z_R
+};
+
+#define BOLTMAP_MASK (sizeof(boltmap) - 1)
+
+void send_steno_state(void) {
+  for (uint8_t i = 0; i < 4; ++i) {
+    if (state[i]) {
+      virtser_send(state[i]);
+      state[i] = 0;
+    }
+  }
+  virtser_send(0);
+}
+
+bool process_steno(uint16_t keycode, keyrecord_t *record) {
+  if(keycode >= QK_STENO && keycode <= QK_STENO_MAX) {
+    if(IS_PRESSED(record->event)) {
+      uint8_t boltcode = boltmap[keycode & BOLTMAP_MASK];
+      ++pressed;
+      state[TXB_GET_GROUP(boltcode)] |= boltcode;
+    } else {
+      --pressed;
+      if (pressed <= 0) {
+        pressed = 0; // protect against spurious up keys
+        send_steno_state();
+      }
+    }
+    return false;
+  }
+
+  return true;
+}
diff --git a/quantum/process_keycode/process_steno.h b/quantum/process_keycode/process_steno.h
new file mode 100644
index 0000000000..fb9b8e8adc
--- /dev/null
+++ b/quantum/process_keycode/process_steno.h
@@ -0,0 +1,12 @@
+#ifndef PROCESS_STENO_H
+#define PROCESS_STENO_H
+
+#include "quantum.h"
+
+#if defined(STENO_ENABLE) && !defined(VIRTSER_ENABLE)
+  #error "must have virtser enabled to use steno"
+#endif
+
+bool process_steno(uint16_t keycode, keyrecord_t *record);
+
+#endif
\ No newline at end of file