[Keyboard] Update Symmetric70 keyboard prototype (#12707)

* update handwired/symmetric70_proto/matrix.c

* make keyboards/handwired/symmetric70_proto/promicro/

* add symmetric70_proto/debug_config.h, update symmetric70_proto/local_features.mk etc.

  set MATRIX_IO_DELAY macro
    make MTEST=mdelay0  symmetric70_proto/promicro:default:flash
    make MTEST=mdelay1  symmetric70_proto/promicro:default:flash
    make MTEST=mdelay10 symmetric70_proto/promicro:default:flash
    make MTEST=mdelay30 symmetric70_proto/promicro:default:flash
  set DEBUG_MATRIX_SCAN_RATE_ENABLE yes
    make MTEST=scan symmetric70_proto/promicro:default:flash
  set MATRIX_DEBUG_DELAY and MATRIX_IO_DELAY macro
    make MTEST=matrix_debug_delay,mdelay0 symmetric70_proto/promicro:default:flash
  set MATRIX_DEBUG_SCAN
    make MTEST=matrix_debug_scan symmetric70_proto/promicro:default:flash

* add symmetric70_proto/matrix_debug/readme.md

* update symmetric70_proto/matrix_debug/readme.md

* update handwired/symmetric70_proto/readme.md

* update handwired/symmetric70_proto/readme.md

* update handwired/symmetric70_proto/*/readme.md

* add handwired/symmetric70_proto/matrix_fast/

* update handwired/symmetric70_proto/matrix_fast/readme.md

* fix typo in handwired/symmetric70_proto/matrix_fast/readme.md

* update config.h under handwired/symmetric70_proto/promicro

* add Proton C support to handwired/symmetric70_proto

* add handwired/symmetric70_proto/proton_c/readme.md

* add promicro/*/readme.md proton_c/*/readme.md

* update handwired/symmetric70_proto/proton_c/proton_c.c

support MATRIX_IO_DELAY_DEFAULT for testing.

* Added another implementation of 'adaptive_delay'.

* update symmetric70_proto/local_features.mk

* update symmetric70_proto/matrix_fast/gpio_extr.h

* add matrix_output_unselect_delay_ports()

* add MTEST=adaptive_delay_fast option

* update symmetric70_proto/matrix_debug/readme.md

* update symmetric70_proto/matrix_fast/readme.md

* update symmetric70_proto/matrix_debug/readme.md

* Erase garbage

* fix symmetric70_proto/proton_c/proton_c.c

* improve adaptive_delay_fast in symmetric70_proto/matrix_debug/matrix.c

* update symmetric70_proto/matrix_debug/readme.md

* fix symmetric70_proto/matrix_debug/readme.md

* Update keyboards/handwired/symmetric70_proto/proton_c/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/handwired/symmetric70_proto/proton_c/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/handwired/symmetric70_proto/local_features.mk

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/local_features.mk

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/local_features.mk

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/readme.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/readme.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/readme.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_fast/matrix_config_expand.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: Nick Brassel <nick@tzarc.org>

3 files changed, 534 insertions, 0 deletions

diff --git a/keyboards/handwired/symmetric70_proto/matrix_debug/gpio_extr.h b/keyboards/handwired/symmetric70_proto/matrix_debug/gpio_extr.h
new file mode 100644
index 0000000000..c7d08309d0
--- /dev/null
+++ b/keyboards/handwired/symmetric70_proto/matrix_debug/gpio_extr.h
@@ -0,0 +1,10 @@
+#pragma once
+// clang-format off
+
+#if defined(__AVR__)
+#    define readPort(port) PINx_ADDRESS(port)
+typedef uint8_t     port_data_t;
+#else
+#    define readPort(qmk_pin) palReadPort(PAL_PORT(qmk_pin))
+typedef uint16_t     port_data_t;
+#endif
diff --git a/keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c b/keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c
new file mode 100644
index 0000000000..c84efe2915
--- /dev/null
+++ b/keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c
@@ -0,0 +1,324 @@
+/*
+Copyright 2012-2018 Jun Wako, Jack Humbert, Yiancar
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include <stdint.h>
+#include <stdbool.h>
+#include "util.h"
+#include "matrix.h"
+#include "debounce.h"
+#include "quantum.h"
+#ifndef readPort
+#    include "gpio_extr.h"
+#endif
+
+#ifndef MATRIX_DEBUG_PIN
+#    define MATRIX_DEBUG_PIN_INIT()
+#    define MATRIX_DEBUG_SCAN_START()
+#    define MATRIX_DEBUG_SCAN_END()
+#    define MATRIX_DEBUG_DELAY_START()
+#    define MATRIX_DEBUG_DELAY_END()
+#    define MATRIX_DEBUG_GAP()
+#else
+#    define MATRIX_DEBUG_GAP()  asm volatile("nop \n nop":::"memory")
+#endif
+
+#ifndef MATRIX_IO_DELAY_ALWAYS
+#    define MATRIX_IO_DELAY_ALWAYS 0
+#endif
+
+#ifdef DIRECT_PINS
+static pin_t direct_pins[MATRIX_ROWS][MATRIX_COLS] = DIRECT_PINS;
+#elif (DIODE_DIRECTION == ROW2COL) || (DIODE_DIRECTION == COL2ROW)
+static const pin_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
+static const pin_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
+#  ifdef MATRIX_MUL_SELECT
+static const pin_t col_sel[MATRIX_COLS] = MATRIX_MUL_SEL;
+#  endif
+#endif
+
+#ifdef MATRIX_IO_DELAY_PORTS
+static const pin_t delay_ports[] = { MATRIX_IO_DELAY_PORTS };
+static const port_data_t delay_masks[] = { MATRIX_IO_DELAY_MASKS };
+#    ifdef MATRIX_IO_DELAY_MULSEL
+static const uint8_t delay_sel[] = { MATRIX_IO_DELAY_MULSEL };
+#    endif
+#endif
+
+/* matrix state(1:on, 0:off) */
+extern matrix_row_t raw_matrix[MATRIX_ROWS];  // raw values
+extern matrix_row_t matrix[MATRIX_ROWS];      // debounced values
+
+static inline void setPinOutput_writeLow(pin_t pin) {
+    ATOMIC_BLOCK_FORCEON {
+        setPinOutput(pin);
+        writePinLow(pin);
+    }
+}
+
+static inline void setPinInputHigh_atomic(pin_t pin) {
+    ATOMIC_BLOCK_FORCEON { setPinInputHigh(pin); }
+}
+
+// matrix code
+
+#ifdef DIRECT_PINS
+
+static void init_pins(void) {
+    for (int row = 0; row < MATRIX_ROWS; row++) {
+        for (int col = 0; col < MATRIX_COLS; col++) {
+            pin_t pin = direct_pins[row][col];
+            if (pin != NO_PIN) {
+                setPinInputHigh(pin);
+            }
+        }
+    }
+}
+
+static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
+    // Start with a clear matrix row
+    matrix_row_t current_row_value = 0;
+
+    for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
+        pin_t pin = direct_pins[current_row][col_index];
+        if (pin != NO_PIN) {
+            current_row_value |= readPin(pin) ? 0 : (MATRIX_ROW_SHIFTER << col_index);
+        }
+    }
+
+    // If the row has changed, store the row and return the changed flag.
+    if (current_matrix[current_row] != current_row_value) {
+        current_matrix[current_row] = current_row_value;
+        return true;
+    }
+    return false;
+}
+
+#elif defined(DIODE_DIRECTION)
+#    if (DIODE_DIRECTION == COL2ROW)
+
+static void select_row(uint8_t row) { setPinOutput_writeLow(row_pins[row]); }
+
+static void unselect_row(uint8_t row) { setPinInputHigh_atomic(row_pins[row]); }
+
+static void unselect_rows(void) {
+    for (uint8_t x = 0; x < MATRIX_ROWS; x++) {
+        setPinInputHigh_atomic(row_pins[x]);
+    }
+}
+
+static void init_pins(void) {
+#ifdef MATRIX_MUL_SELECT
+    setPinOutput(MATRIX_MUL_SELECT);
+    writePinLow(MATRIX_MUL_SELECT);
+#endif
+    unselect_rows();
+    for (uint8_t x = 0; x < MATRIX_COLS; x++) {
+        setPinInputHigh_atomic(col_pins[x]);
+    }
+}
+
+static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
+    // Start with a clear matrix row
+    matrix_row_t current_row_value = 0;
+
+    // Select row
+    select_row(current_row);
+    matrix_output_select_delay();
+
+    // For each col...
+    for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
+        // Select the col pin to read (active low)
+#ifdef MATRIX_MUL_SELECT
+        writePin(MATRIX_MUL_SELECT,col_sel[col_index]);
+        waitInputPinDelay();
+#endif
+        uint8_t pin_state = readPin(col_pins[col_index]);
+
+        // Populate the matrix row with the state of the col pin
+        current_row_value |= pin_state ? 0 : (MATRIX_ROW_SHIFTER << col_index);
+    }
+
+    // Unselect row
+    unselect_row(current_row);
+#ifdef MATRIX_IO_DELAY_PORTS
+    if (current_row_value) {  // wait for col signal to go HIGH
+        bool is_pressed;
+        do {
+            MATRIX_DEBUG_DELAY_START();
+            is_pressed = false;
+            for (uint8_t i = 0; i < sizeof(delay_ports)/sizeof(pin_t); i++ ) {
+#    ifdef MATRIX_IO_DELAY_MULSEL
+                writePin(MATRIX_MUL_SELECT, delay_sel[i]);
+                waitInputPinDelay();
+#    endif
+                is_pressed |= ( (readPort(delay_ports[i]) & delay_masks[i]) != delay_masks[i] );
+            }
+            MATRIX_DEBUG_DELAY_END();
+        } while (is_pressed);
+    }
+#endif
+#ifdef MATRIX_IO_DELAY_ADAPTIVE
+    if (current_row_value) {  // wait for col signal to go HIGH
+        for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
+            MATRIX_DEBUG_DELAY_START();
+#ifdef MATRIX_MUL_SELECT
+            writePin(MATRIX_MUL_SELECT,col_sel[col_index]);
+            waitInputPinDelay();
+#endif
+            while (readPin(col_pins[col_index]) == 0) {}
+            MATRIX_DEBUG_DELAY_END();
+        }
+    }
+#endif
+#ifdef MATRIX_IO_DELAY_ADAPTIVE2
+    if (current_row_value) {  // wait for col signal to go HIGH
+        pin_t state;
+        do {
+            MATRIX_DEBUG_DELAY_START();
+            state = 0;
+            for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
+                MATRIX_DEBUG_DELAY_END();
+                MATRIX_DEBUG_DELAY_START();
+#ifdef MATRIX_MUL_SELECT
+                writePin(MATRIX_MUL_SELECT,col_sel[col_index]);
+                waitInputPinDelay();
+#endif
+                state |= (readPin(col_pins[col_index]) == 0);
+            }
+            MATRIX_DEBUG_DELAY_END();
+        } while (state);
+    }
+#endif
+    if (MATRIX_IO_DELAY_ALWAYS || current_row + 1 < MATRIX_ROWS) {
+        MATRIX_DEBUG_DELAY_START();
+        matrix_output_unselect_delay();  // wait for col signal to go HIGH
+        MATRIX_DEBUG_DELAY_END();
+    }
+
+    // If the row has changed, store the row and return the changed flag.
+    if (current_matrix[current_row] != current_row_value) {
+        current_matrix[current_row] = current_row_value;
+        return true;
+    }
+    return false;
+}
+
+#    elif (DIODE_DIRECTION == ROW2COL)
+
+static void select_col(uint8_t col) { setPinOutput_writeLow(col_pins[col]); }
+
+static void unselect_col(uint8_t col) { setPinInputHigh_atomic(col_pins[col]); }
+
+static void unselect_cols(void) {
+    for (uint8_t x = 0; x < MATRIX_COLS; x++) {
+        setPinInputHigh_atomic(col_pins[x]);
+    }
+}
+
+static void init_pins(void) {
+    unselect_cols();
+    for (uint8_t x = 0; x < MATRIX_ROWS; x++) {
+        setPinInputHigh_atomic(row_pins[x]);
+    }
+}
+
+static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
+    bool matrix_changed = false;
+
+    // Select col
+    select_col(current_col);
+    matrix_output_select_delay();
+
+    // For each row...
+    for (uint8_t row_index = 0; row_index < MATRIX_ROWS; row_index++) {
+        // Store last value of row prior to reading
+        matrix_row_t last_row_value    = current_matrix[row_index];
+        matrix_row_t current_row_value = last_row_value;
+
+        // Check row pin state
+        if (readPin(row_pins[row_index]) == 0) {
+            // Pin LO, set col bit
+            current_row_value |= (MATRIX_ROW_SHIFTER << current_col);
+        } else {
+            // Pin HI, clear col bit
+            current_row_value &= ~(MATRIX_ROW_SHIFTER << current_col);
+        }
+
+        // Determine if the matrix changed state
+        if ((last_row_value != current_row_value)) {
+            matrix_changed |= true;
+            current_matrix[row_index] = current_row_value;
+        }
+    }
+
+    // Unselect col
+    unselect_col(current_col);
+    if (MATRIX_IO_DELAY_ALWAYS || current_col + 1 < MATRIX_COLS) {
+        matrix_output_unselect_delay();  // wait for col signal to go HIGH
+    }
+
+    return matrix_changed;
+}
+
+#    else
+#        error DIODE_DIRECTION must be one of COL2ROW or ROW2COL!
+#    endif
+#else
+#    error DIODE_DIRECTION is not defined!
+#endif
+
+void matrix_init(void) {
+    // initialize key pins
+    init_pins();
+
+    // initialize matrix state: all keys off
+    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+        raw_matrix[i] = 0;
+        matrix[i]     = 0;
+    }
+
+    debounce_init(MATRIX_ROWS);
+
+    matrix_init_quantum();
+}
+
+uint8_t matrix_scan(void) {
+    bool changed = false;
+    MATRIX_DEBUG_PIN_INIT();
+
+    MATRIX_DEBUG_SCAN_START();
+#if defined(DIRECT_PINS) || (DIODE_DIRECTION == COL2ROW)
+    // Set row, read cols
+    for (uint8_t current_row = 0; current_row < MATRIX_ROWS; current_row++) {
+        changed |= read_cols_on_row(raw_matrix, current_row);
+    }
+#elif (DIODE_DIRECTION == ROW2COL)
+    // Set col, read rows
+    for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
+        changed |= read_rows_on_col(raw_matrix, current_col);
+    }
+#endif
+    MATRIX_DEBUG_SCAN_END(); MATRIX_DEBUG_GAP();
+
+    MATRIX_DEBUG_SCAN_START();
+    debounce(raw_matrix, matrix, MATRIX_ROWS, changed);
+    MATRIX_DEBUG_SCAN_END(); MATRIX_DEBUG_GAP();
+
+    MATRIX_DEBUG_SCAN_START();
+    matrix_scan_quantum();
+    MATRIX_DEBUG_SCAN_END();
+    return (uint8_t)changed;
+}
diff --git a/keyboards/handwired/symmetric70_proto/matrix_debug/readme.md b/keyboards/handwired/symmetric70_proto/matrix_debug/readme.md
new file mode 100644
index 0000000000..3e45db87e9
--- /dev/null
+++ b/keyboards/handwired/symmetric70_proto/matrix_debug/readme.md
@@ -0,0 +1,200 @@
+# Debug version matrix.c
+
+This matrix.c is quantum/matrix.c with the following additions:
+
+* Added the MATRIX_DEBUG_SCAN_{START/END} macro to measure the execution time of matrix_scan().
+* Added the MATRIX_DEBUG_DELAY_{START/END} macro to measure delay time.
+* Added the MATRIX_MUL_SELECT handling for symmetric70_proto.
+
+## Compile
+
+* Set MATRIX_IO_DELAY value
+  * `make MTEST=mdelay0 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=1 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=2 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=3 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=4 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=5 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=10 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=20 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=mdelay=30 handwired/symmetric70_proto/promicro/normal:default:flash`
+* Measure the execution time of matrix_scan()
+  * `make MTEST=matrix_debug_scan[,<other options>..] handwired/symmetric70_proto/promicro/normal:default:flash`
+* Measure delay time.
+  * `make MTEST=matrix_debug_delay[,<other options>..] handwired/symmetric70_proto/promicro/normal:default:flash`
+* Change the behavior of delay
+  * `make MTEST=matrix_debug_delay,always_delay handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=matrix_debug_delay,adaptive_delay,mdelay0 handwired/symmetric70_proto/promicro/normal:default:flash`
+  * `make MTEST=matrix_debug_delay,adaptive_delay_fast,mdelay0 handwired/symmetric70_proto/promicro/normal:default:flash`
+
+## Measurement result
+### Pro Micro (ATmega32u4 16Mhz)
+#### Default setting (show `matrix_scan()` time)
+ - `make MTEST=matrix_debug_scan handwired/symmetric70_proto/promicro/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  503us
+ - Frequency of matrix scan 1.81kHz (551.0us)  
+   ![DS1Z_QuickPrint2](https://user-images.githubusercontent.com/2170248/115994477-0ba64400-a612-11eb-98ba-b8cc362f26ac.png)
+
+#### Always call `matrix_output_unselect_delay()` (show `matrix_scan()` time, default MATRIX_IO_DELAY)
+ - `make MTEST=matrix_debug_scan,always_delay handwired/symmetric70_proto/promicro/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  521us
+ - Frequency of matrix scan 1.76kHz (568.5us)  
+   ![DS1Z_QuickPrint1](https://user-images.githubusercontent.com/2170248/115994488-1660d900-a612-11eb-83b1-cd820607db03.png)
+
+#### Adaptive delay (show `matrix_scan()` time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_scan,mdelay0,adaptive_delay handwired/symmetric70_proto/promicro/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  383us
+ - Frequency of matrix scan 2.32kHz (431us)  
+   ![DS1Z_QuickPrint3](https://user-images.githubusercontent.com/2170248/115994939-034f0880-a614-11eb-861f-b83a31efa51a.png)
+
+#### Adaptive delay (show delay time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_delay,mdelay0,adaptive_delay handwired/symmetric70_proto/promicro/normal:default:flash`
+
+##### Press R0C1, R1C1 key
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: delay time
+ - Delay time 68us
+ - Frequency of matrix scan 1.77kHz (565us)  
+   ![DS1Z_QuickPrint55](https://user-images.githubusercontent.com/2170248/119561268-ead33900-bddf-11eb-9cc4-7e04826486cf.png)
+
+#### Fast adaptive delay (show `matrix_scan()` time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_scan,mdelay0,adaptive_delay_fast handwired/symmetric70_proto/promicro/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  382us
+ - Frequency of matrix scan 2.33kHz (428us)  
+   ![DS1Z_QuickPrint56](https://user-images.githubusercontent.com/2170248/119561280-eeff5680-bddf-11eb-9576-e4cf64751955.png)
+
+#### Fast adaptive delay (show delay time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_delay,mdelay0,adaptive_delay_fast handwired/symmetric70_proto/promicro/normal:default:flash`
+
+##### Press R0C1, R1C1 key
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: delay time
+ - Delay time 11us
+ - Frequency of matrix scan 2.21kHz (452us)  
+   ![DS1Z_QuickPrint57](https://user-images.githubusercontent.com/2170248/119561318-faeb1880-bddf-11eb-8592-694f9ecb2248.png)
+
+### Proton C (STM32F303 72MHz)
+#### Default setting (show `matrix_scan()` time)
+ - `make MTEST=matrix_debug_scan handwired/symmetric70_proto/proton_c/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  210us
+ - Frequency of matrix scan 4.35kHz (230.0us)  
+   ![DS1Z_QuickPrint16](https://user-images.githubusercontent.com/2170248/116131295-2ad2cd80-a707-11eb-8d0a-6f7912456e03.png)
+
+#### Always call `matrix_output_unselect_delay()` (show `matrix_scan()` time, default MATRIX_IO_DELAY)
+ - `make MTEST=matrix_debug_scan,always_delay handwired/symmetric70_proto/proton_c/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  242us
+ - Frequency of matrix scan 3.85kHz (260.0us)  
+   ![DS1Z_QuickPrint17](https://user-images.githubusercontent.com/2170248/116131308-31f9db80-a707-11eb-8db7-d1960fa7b068.png)
+
+#### Adaptive delay (show `matrix_scan()` time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_scan,mdelay0,adaptive_delay handwired/symmetric70_proto/proton_c/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  76.4us
+ - Frequency of matrix scan 10.6kHz (94.4us)  
+   ![DS1Z_QuickPrint18](https://user-images.githubusercontent.com/2170248/116131369-44741500-a707-11eb-9c74-fa39d9e80947.png)
+
+#### Adaptive delay (show delay time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_delay,mdelay0,adaptive_delay handwired/symmetric70_proto/proton_c/normal:default:flash`
+
+##### Press R0C1, R1C1 key
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: delay time
+ - Delay time 7.6us
+ - Frequency of matrix scan 9.47kHz (105.6us)  
+   ![DS1Z_QuickPrint58](https://user-images.githubusercontent.com/2170248/119666783-a3e15400-be70-11eb-9a58-220032117efd.png)
+
+##### Connect a 500pF capacitor between C2 line and GND, Press R0C2, R1C2, R2C2, R3C2, R4C2 keys
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Col 2
+ - CH4: delay time
+ - Delay time 12us + alpha
+ - Frequency of matrix scan 5.45kHz (183us)
+ - Threshold Voltage 1.9V  
+   ![DS1Z_QuickPrint59](https://user-images.githubusercontent.com/2170248/119666946-cc694e00-be70-11eb-9b97-4c500416d774.png)
+
+##### Connect a 1000pF capacitor between C2 line and GND, Press R0C2, R1C2, R2C2, R3C2, R4C2 keys
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Col 2
+ - CH4: delay time
+ - Delay time 20us + alpha
+ - Frequency of matrix scan 4.48kHz (223us)
+ - Threshold Voltage 1.9V  
+   ![DS1Z_QuickPrint60](https://user-images.githubusercontent.com/2170248/119667127-f3c01b00-be70-11eb-8e7f-6f0a81f95e97.png)
+
+#### Fast adaptive delay (show `matrix_scan()` time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_scan,mdelay0,adaptive_delay_fast handwired/symmetric70_proto/proton_c/normal:default:flash`
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: matrix_scan()
+ - Execution time of matrix_scan()  75.6us
+ - Frequency of matrix scan 10.8kHz (92.2us)  
+   ![DS1Z_QuickPrint62](https://user-images.githubusercontent.com/2170248/119667218-0b979f00-be71-11eb-946c-16f0a0454056.png)
+
+#### Fast adaptive delay (show delay time, MATRIX_IO_DELAY = 0)
+ - `make MTEST=matrix_debug_delay,mdelay0,adaptive_delay_fast handwired/symmetric70_proto/proton_c/normal:default:flash`
+
+##### Press R0C1, R1C1 key
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Row 4
+ - CH4: delay time
+ - Delay time 1.6us
+ - Frequency of matrix scan 10.6kHz (94.4us)  
+   ![DS1Z_QuickPrint63](https://user-images.githubusercontent.com/2170248/119667378-33870280-be71-11eb-95aa-64213138ddac.png)
+   ![DS1Z_QuickPrint64](https://user-images.githubusercontent.com/2170248/119667504-52859480-be71-11eb-963e-eebc6e3da9dc.png)
+
+##### Connect a 500pF capacitor between C2 line and GND, Press R0C2, R1C2, R2C2, R3C2, R4C2 keys
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Col 2
+ - CH4: delay time
+ - Delay time 13.2us
+ - Frequency of matrix scan 6.58kHz (152.6us)
+ - Threshold Voltage 1.9V  
+   ![DS1Z_QuickPrint65](https://user-images.githubusercontent.com/2170248/119667644-72b55380-be71-11eb-8030-854de1900408.png)
+
+##### Connect a 1000pF capacitor between C2 line and GND, Press R0C2, R1C2, R2C2, R3C2, R4C2 keys
+ - CH1: Row 0
+ - CH2: Row 1
+ - CH3: Col 2
+ - CH4: delay time
+ - Delay time 20us
+ - Frequency of matrix scan 5.30kHz (188.8us)
+ - Threshold Voltage 1.9V  
+   ![DS1Z_QuickPrint66](https://user-images.githubusercontent.com/2170248/119667785-8f518b80-be71-11eb-8d40-fc3293aa072b.png)