don't remember seeing mention of display in previous posts
this is using a CYD to display pulse count etc (input 1MHz)
main.ino
// ESP32 - count pulses and display on CYD TFT
// Arduino forum https://forum.arduino.cc/t/please-help-me-understand-this-code/1381333/9
#include <TFT_eSPI.h>
#include <TFT_eSPI_Scroll.h>
#include <4bit.h>
TFT_eSPI tft;
TFT_eSPI_Scroll scroll;
// 1. measure pulse width and rising edge-to-edge time using GPIO 16 and 17
// 2. using PCNT count pulses on GPIO 4 while signal on GPIO 16 is high
// https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/peripherals/pcnt.html
#include "driver/pulse_cnt.h"
#include "driver/gpio.h"
#include "esp_err.h"
// define input GPIO pins
#define PULSE_COUNT_PIN 35 // measure pulse count
#define PULSE_LEVEL_PIN_1 22 // measure pulse width and rising edge-to-edge time
#define PULSE_LEVEL_PIN_2 27
// PCNT pulse counter definitions
#define EXAMPLE_PCNT_HIGH_LIMIT 20000
#define EXAMPLE_PCNT_LOW_LIMIT -100
pcnt_unit_config_t unit_config = {
.low_limit = EXAMPLE_PCNT_LOW_LIMIT,
.high_limit = EXAMPLE_PCNT_HIGH_LIMIT,
.flags = {
.accum_count = 1,
}
};
pcnt_unit_handle_t pcnt_unit = NULL;
pcnt_chan_config_t chan_config = {
.edge_gpio_num = PULSE_COUNT_PIN,
.level_gpio_num = PULSE_LEVEL_PIN_1,
};
pcnt_channel_handle_t pcnt_chan = NULL;
// timer to measure pulse width and rising edge-to-edge time
hw_timer_t *Timer1_Cfg = NULL; // timer object
// pulse timing data
volatile uint64_t riseTime, period, width;
// rising edge interrupt calculate period uSec
void IRAM_ATTR rising() {
//pcnt_unit_clear_count(pcnt_unit); // clear PCNT count
uint64_t rise = timerReadMicros(Timer1_Cfg);
period = rise - riseTime; // calculate period
riseTime = rise;
}
// falling edge interrupt calculate pulse width uSec
volatile bool newPulse = false;
void IRAM_ATTR falling() {
uint64_t fall = timerReadMicros(Timer1_Cfg);
width = fall - riseTime; // calculate pulse width
newPulse = true; // indicate new data
}
void setup(void) {
Serial.begin(115200);
delay(2000);
Serial.println("\n\nESP32 pulse counter using PCNT unit");
Serial.println("setup timer and GPIO interrupts");
if ((Timer1_Cfg = timerBegin(1000000)) == NULL) // API 3.0 setup timer for 1uSec
Serial.println("timerBegin Failed!!");
Serial.print("timerBegin() OK frequenmcy ");
Serial.println(timerGetFrequency(Timer1_Cfg));
// setup interrput routines - connect signal to pins 16 and 17
attachInterrupt(digitalPinToGPIONumber(PULSE_LEVEL_PIN_1), rising, RISING); // detect rising edge on pin 16
attachInterrupt(digitalPinToGPIONumber(PULSE_LEVEL_PIN_2), falling, FALLING); // detect falling edge on pin 17
Serial.println("Setup PCNT (pulse Counter) ");
Serial.println("install pcnt unit");
ESP_ERROR_CHECK(pcnt_new_unit(&unit_config, &pcnt_unit));
Serial.println("install pcnt channels");
ESP_ERROR_CHECK(pcnt_new_channel(pcnt_unit, &chan_config, &pcnt_chan));
Serial.println("set edge and level actions for pcnt channels");
ESP_ERROR_CHECK(pcnt_channel_set_edge_action(pcnt_chan, PCNT_CHANNEL_EDGE_ACTION_HOLD, PCNT_CHANNEL_EDGE_ACTION_INCREASE));
ESP_ERROR_CHECK(pcnt_channel_set_level_action(pcnt_chan, PCNT_CHANNEL_LEVEL_ACTION_KEEP, PCNT_CHANNEL_LEVEL_ACTION_HOLD));
Serial.println("add watch point");
ESP_ERROR_CHECK(pcnt_unit_add_watch_point(pcnt_unit, EXAMPLE_PCNT_HIGH_LIMIT));
Serial.println("enable pcnt unit");
ESP_ERROR_CHECK(pcnt_unit_enable(pcnt_unit));
Serial.println("clear pcnt unit");
ESP_ERROR_CHECK(pcnt_unit_clear_count(pcnt_unit));
Serial.println("start pcnt unit");
ESP_ERROR_CHECK(pcnt_unit_start(pcnt_unit));
// setup TFT
tft.init();
// Initializing the tft_espi_scroll int 1bit B/W
if (scroll.init(&tft, 4) != NO_ERROR) {
Serial.println("Failed... Reseting...");
return;
}
String data = String("TFT setup");
scroll.write(data);
}
// display pulse count on falling edge of GPIO 16
void loop() {
if (!newPulse) return; // on pulse falling edge display results
newPulse = false;
static int pulse_count_old = 0, pulse_count = 0;
pcnt_unit_get_count(pcnt_unit, &pulse_count); // read PCNT pulse count
Serial.printf("test Pulse count: %d frequency %dHz\n", pulse_count - pulse_count_old, (pulse_count - pulse_count_old) * 10000);
//pulse_count_old = pulse_count;
Serial.printf("period %llduSec width = %llduSec frequency %.2fHz\n",
period, width, 1000000.0 / period);
// display on TFT
scroll.reset();
if (scroll.init(&tft, 4) != NO_ERROR) {
Serial.println("Failed... Reseting...");
return;
}
char text[500] = { 0 };
sprintf(text, "Pulse count: %d\n freq %dHz\n\n", pulse_count - pulse_count_old, (pulse_count - pulse_count_old) * 10000);
scroll.write(text);
text[0] = 0;
pulse_count_old = pulse_count;
sprintf(text, "\nperiod %llduSec\n width = %llduSec\n freq %.2fHz\n\n",
period, width, 1000000.0 / period);
scroll.write(text);
}
User_Setup.h (in samr directory as about main.ino file)
// USER DEFINED SETTINGS
// Set driver type, fonts to be loaded, pins used and SPI control method etc
//
// See the User_Setup_Select.h file if you wish to be able to define multiple
// setups and then easily select which setup file is used by the compiler.
//
// If this file is edited correctly then all the library example sketches should
// run without the need to make any more changes for a particular hardware setup!
// Note that some sketches are designed for a particular TFT pixel width/height
// ##################################################################################
//
// Section 1. Call up the right driver file and any options for it
//
// ##################################################################################
// Define STM32 to invoke optimised processor support (only for STM32)
//#define STM32
// Defining the STM32 board allows the library to optimise the performance
// for UNO compatible "MCUfriend" style shields
//#define NUCLEO_64_TFT
//#define NUCLEO_144_TFT
// STM32 8 bit parallel only:
// If STN32 Port A or B pins 0-7 are used for 8 bit parallel data bus bits 0-7
// then this will improve rendering performance by a factor of ~8x
//#define STM_PORTA_DATA_BUS
//#define STM_PORTB_DATA_BUS
// Tell the library to use 8 bit parallel mode (otherwise SPI is assumed)
//#define TFT_PARALLEL_8_BIT
// Display type - only define if RPi display
//#define RPI_DISPLAY_TYPE // 20MHz maximum SPI
// Only define one driver, the other ones must be commented out
//#define ILI9341_DRIVER // Generic driver for common displays
#define ILI9341_2_DRIVER // Alternative ILI9341 driver, see https://github.com/Bodmer/TFT_eSPI/issues/1172
//#define ST7735_DRIVER // Define additional parameters below for this display
//#define ILI9163_DRIVER // Define additional parameters below for this display
//#define S6D02A1_DRIVER
//#define RPI_ILI9486_DRIVER // 20MHz maximum SPI
//#define HX8357D_DRIVER
//#define ILI9481_DRIVER
//#define ILI9486_DRIVER
//define ILI9488_DRIVER // WARNING: Do not connect ILI9488 display SDO to MISO if other devices share the SPI bus (TFT SDO does NOT tristate when CS is high)
//#define ST7789_DRIVER // Full configuration option, define additional parameters below for this display
//#define ST7789_2_DRIVER // Minimal configuration option, define additional parameters below for this display
//#define R61581_DRIVER
//#define RM68140_DRIVER
//#define ST7796_DRIVER
//#define SSD1351_DRIVER
//#define SSD1963_480_DRIVER
//#define SSD1963_800_DRIVER
//#define SSD1963_800ALT_DRIVER
//#define ILI9225_DRIVER
//#define GC9A01_DRIVER
// Some displays support SPI reads via the MISO pin, other displays have a single
// bi-directional SDA pin and the library will try to read this via the MOSI line.
// To use the SDA line for reading data from the TFT uncomment the following line:
// #define TFT_SDA_READ // This option is for ESP32 ONLY, tested with ST7789 and GC9A01 display only
// For ST7735, ST7789 and ILI9341 ONLY, define the colour order IF the blue and red are swapped on your display
// Try ONE option at a time to find the correct colour order for your display
// #define TFT_RGB_ORDER TFT_RGB // Colour order Red-Green-Blue
// #define TFT_RGB_ORDER TFT_BGR // Colour order Blue-Green-Red
// For M5Stack ESP32 module with integrated ILI9341 display ONLY, remove // in line below
// #define M5STACK
// For ST7789, ST7735, ILI9163 and GC9A01 ONLY, define the pixel width and height in portrait orientation
// #define TFT_WIDTH 80
// #define TFT_WIDTH 128
// #define TFT_WIDTH 128 // ST7789 240 x 240 and 240 x 320
#define TFT_WIDTH 240
// #define TFT_WIDTH 320
// #define TFT_HEIGHT 160
// #define TFT_HEIGHT 128
//#define TFT_HEIGHT 160 // ST7789 240 x 240
#define TFT_HEIGHT 320 // ST7789 240 x 320
// #define TFT_HEIGHT 240 // GC9A01 240 x 240 //#define TFT_HEIGHT 480
// For ST7735 ONLY, define the type of display, originally this was based on the
// colour of the tab on the screen protector film but this is not always true, so try
// out the different options below if the screen does not display graphics correctly,
// e.g. colours wrong, mirror images, or stray pixels at the edges.
// Comment out ALL BUT ONE of these options for a ST7735 display driver, save this
// this User_Setup file, then rebuild and upload the sketch to the board again:
// #define ST7735_INITB
// #define ST7735_GREENTAB
// #define ST7735_GREENTAB2
// #define ST7735_GREENTAB3
// #define ST7735_GREENTAB128 // For 128 x 128 display
// #define ST7735_GREENTAB160x80 // For 160 x 80 display (BGR, inverted, 26 offset)
// #define ST7735_REDTAB
// #define ST7735_BLACKTAB
// #define ST7735_REDTAB160x80 // For 160 x 80 display with 24 pixel offset
// If colours are inverted (white shows as black) then uncomment one of the next
// 2 lines try both options, one of the options should correct the inversion.
// #define TFT_INVERSION_ON
// #define TFT_INVERSION_OFF
// ##################################################################################
//
// Section 2. Define the pins that are used to interface with the display here
//
// ##################################################################################
// If a backlight control signal is available then define the TFT_BL pin in Section 2
// below. The backlight will be turned ON when tft.begin() is called, but the library
// needs to know if the LEDs are ON with the pin HIGH or LOW. If the LEDs are to be
// driven with a PWM signal or turned OFF/ON then this must be handled by the user
// sketch. e.g. with digitalWrite(TFT_BL, LOW);
#define TFT_BL 21 // LED back-light control pin
#define TFT_BACKLIGHT_ON HIGH // Level to turn ON back-light (HIGH or LOW)
// We must use hardware SPI, a minimum of 3 GPIO pins is needed.
// Typical setup for ESP8266 NodeMCU ESP-12 is :
//
// Display SDO/MISO to NodeMCU pin D6 (or leave disconnected if not reading TFT)
// Display LED to NodeMCU pin VIN (or 5V, see below)
// Display SCK to NodeMCU pin D5
// Display SDI/MOSI to NodeMCU pin D7
// Display DC (RS/AO)to NodeMCU pin D3
// Display RESET to NodeMCU pin D4 (or RST, see below)
// Display CS to NodeMCU pin D8 (or GND, see below)
// Display GND to NodeMCU pin GND (0V)
// Display VCC to NodeMCU 5V or 3.3V
//
// The TFT RESET pin can be connected to the NodeMCU RST pin or 3.3V to free up a control pin
//
// The DC (Data Command) pin may be labelled AO or RS (Register Select)
//
// With some displays such as the ILI9341 the TFT CS pin can be connected to GND if no more
// SPI devices (e.g. an SD Card) are connected, in this case comment out the #define TFT_CS
// line below so it is NOT defined. Other displays such at the ST7735 require the TFT CS pin
// to be toggled during setup, so in these cases the TFT_CS line must be defined and connected.
//
// The NodeMCU D0 pin can be used for RST
//
//
// Note: only some versions of the NodeMCU provide the USB 5V on the VIN pin
// If 5V is not available at a pin you can use 3.3V but backlight brightness
// will be lower.
// ###### EDIT THE PIN NUMBERS IN THE LINES FOLLOWING TO SUIT YOUR ESP8266 SETUP ######
// For NodeMCU - use pin numbers in the form PIN_Dx where Dx is the NodeMCU pin designation
//#define TFT_CS PIN_D8 // Chip select control pin D8
//#define TFT_DC PIN_D3 // Data Command control pin
//#define TFT_RST PIN_D4 // Reset pin (could connect to NodeMCU RST, see next line)
//#define TFT_RST -1 // Set TFT_RST to -1 if the display RESET is connected to NodeMCU RST or 3.3V
//#define TFT_BL PIN_D1 // LED back-light (only for ST7789 with backlight control pin)
//#define TOUCH_CS PIN_D2 // Chip select pin (T_CS) of touch screen
//#define TFT_WR PIN_D2 // Write strobe for modified Raspberry Pi TFT only
// ###### FOR ESP8266 OVERLAP MODE EDIT THE PIN NUMBERS IN THE FOLLOWING LINES ######
// Overlap mode shares the ESP8266 FLASH SPI bus with the TFT so has a performance impact
// but saves pins for other functions. It is best not to connect MISO as some displays
// do not tristate that line when chip select is high!
// On NodeMCU 1.0 SD0=MISO, SD1=MOSI, CLK=SCLK to connect to TFT in overlap mode
// On NodeMCU V3 S0 =MISO, S1 =MOSI, S2 =SCLK
// In ESP8266 overlap mode the following must be defined
//#define TFT_SPI_OVERLAP
// In ESP8266 overlap mode the TFT chip select MUST connect to pin D3
//#define TFT_CS PIN_D3
//#define TFT_DC PIN_D5 // Data Command control pin
//#define TFT_RST PIN_D4 // Reset pin (could connect to NodeMCU RST, see next line)
//#define TFT_RST -1 // Set TFT_RST to -1 if the display RESET is connected to NodeMCU RST or 3.3V
// ###### EDIT THE PIN NUMBERS IN THE LINES FOLLOWING TO SUIT YOUR ESP32 SETUP ######
// For ESP32 Dev board (only tested with ILI9341 display)
// The hardware SPI can be mapped to any pins
// #define TFT_MISO -1
// #define TFT_MOSI 14
// #define TFT_SCLK 33
// #define TFT_CS -1 // Chip select control pin
// #define TFT_DC 13 // Data Command control pin
// #define TFT_RST 12 // Reset pin (could connect to RST pin)
//#define TFT_RST -1 // Set TFT_RST to -1 if display RESET is connected to ESP32 board RST
// For ESP32 Dev board (only tested with GC9A01 display)
// The hardware SPI can be mapped to any pins
#define TFT_MOSI 13 // In some display driver board, it might be written as "SDA" and so on.
#define TFT_SCLK 14
#define TFT_CS 15 // Chip select control pin
#define TFT_DC 2 // Data Command control pin
#define TFT_RST 12 // Reset pin (could connect to Arduino RESET pin)
#define TFT_BL 21 // LED back-light
#define TOUCH_CS 33 // Chip select pin (T_CS) of touch screen
//#define TFT_WR 22 // Write strobe for modified Raspberry Pi TFT only
// For the M5Stack module use these #define lines
//#define TFT_MISO 19
//#define TFT_MOSI 23
//#define TFT_SCLK 18
//#define TFT_CS 14 // Chip select control pin
//#define TFT_DC 27 // Data Command control pin
//#define TFT_RST 33 // Reset pin (could connect to Arduino RESET pin)
//#define TFT_BL 32 // LED back-light (required for M5Stack)
// ###### EDIT THE PINs BELOW TO SUIT YOUR ESP32 PARALLEL TFT SETUP ######
// The library supports 8 bit parallel TFTs with the ESP32, the pin
// selection below is compatible with ESP32 boards in UNO format.
// Wemos D32 boards need to be modified, see diagram in Tools folder.
// Only ILI9481 and ILI9341 based displays have been tested!
// Parallel bus is only supported for the STM32 and ESP32
// Example below is for ESP32 Parallel interface with UNO displays
// Tell the library to use 8 bit parallel mode (otherwise SPI is assumed)
//#define TFT_PARALLEL_8_BIT
// The ESP32 and TFT the pins used for testing are:
//#define TFT_CS 33 // Chip select control pin (library pulls permanently low
//#define TFT_DC 15 // Data Command control pin - must use a pin in the range 0-31
//#define TFT_RST 32 // Reset pin, toggles on startup
//#define TFT_WR 4 // Write strobe control pin - must use a pin in the range 0-31
//#define TFT_RD 2 // Read strobe control pin
//#define TFT_D0 12 // Must use pins in the range 0-31 for the data bus
//#define TFT_D1 13 // so a single register write sets/clears all bits.
//#define TFT_D2 26 // Pins can be randomly assigned, this does not affect
//#define TFT_D3 25 // TFT screen update performance.
//#define TFT_D4 17
//#define TFT_D5 16
//#define TFT_D6 27
//#define TFT_D7 14
// ###### EDIT THE PINs BELOW TO SUIT YOUR STM32 SPI TFT SETUP ######
// The TFT can be connected to SPI port 1 or 2
//#define TFT_SPI_PORT 1 // SPI port 1 maximum clock rate is 55MHz
//#define TFT_MOSI PA7
//#define TFT_MISO PA6
//#define TFT_SCLK PA5
//#define TFT_SPI_PORT 2 // SPI port 2 maximum clock rate is 27MHz
//#define TFT_MOSI PB15
//#define TFT_MISO PB14
//#define TFT_SCLK PB13
// Can use Ardiuno pin references, arbitrary allocation, TFT_eSPI controls chip select
//#define TFT_CS D5 // Chip select control pin to TFT CS
//#define TFT_DC D6 // Data Command control pin to TFT DC (may be labelled RS = Register Select)
//#define TFT_RST D7 // Reset pin to TFT RST (or RESET)
// OR alternatively, we can use STM32 port reference names PXnn
//#define TFT_CS PE11 // Nucleo-F767ZI equivalent of D5
//#define TFT_DC PE9 // Nucleo-F767ZI equivalent of D6
//#define TFT_RST PF13 // Nucleo-F767ZI equivalent of D7
//#define TFT_RST -1 // Set TFT_RST to -1 if the display RESET is connected to processor reset
// Use an Arduino pin for initial testing as connecting to processor reset
// may not work (pulse too short at power up?)
// ##################################################################################
//
// Section 3. Define the fonts that are to be used here
//
// ##################################################################################
// Comment out the #defines below with // to stop that font being loaded
// The ESP8366 and ESP32 have plenty of memory so commenting out fonts is not
// normally necessary. If all fonts are loaded the extra FLASH space required is
// about 17Kbytes. To save FLASH space only enable the fonts you need!
#define LOAD_GLCD // Font 1. Original Adafruit 8 pixel font needs ~1820 bytes in FLASH
#define LOAD_FONT2 // Font 2. Small 16 pixel high font, needs ~3534 bytes in FLASH, 96 characters
#define LOAD_FONT4 // Font 4. Medium 26 pixel high font, needs ~5848 bytes in FLASH, 96 characters
#define LOAD_FONT6 // Font 6. Large 48 pixel font, needs ~2666 bytes in FLASH, only characters 1234567890:-.apm
#define LOAD_FONT7 // Font 7. 7 segment 48 pixel font, needs ~2438 bytes in FLASH, only characters 1234567890:-.
#define LOAD_FONT8 // Font 8. Large 75 pixel font needs ~3256 bytes in FLASH, only characters 1234567890:-.
//#define LOAD_FONT8N // Font 8. Alternative to Font 8 above, slightly narrower, so 3 digits fit a 160 pixel TFT
#define LOAD_GFXFF // FreeFonts. Include access to the 48 Adafruit_GFX free fonts FF1 to FF48 and custom fonts
// Comment out the #define below to stop the SPIFFS filing system and smooth font code being loaded
// this will save ~20kbytes of FLASH
#define SMOOTH_FONT
// ##################################################################################
//
// Section 4. Other options
//
// ##################################################################################
// Define the SPI clock frequency, this affects the graphics rendering speed. Too
// fast and the TFT driver will not keep up and display corruption appears.
// With an ILI9341 display 40MHz works OK, 80MHz sometimes fails
// With a ST7735 display more than 27MHz may not work (spurious pixels and lines)
// With an ILI9163 display 27 MHz works OK.
// #define SPI_FREQUENCY 1000000
// #define SPI_FREQUENCY 5000000
//#define SPI_FREQUENCY 10000000
//#define SPI_FREQUENCY 20000000
//#define SPI_FREQUENCY 27000000
//#define SPI_FREQUENCY 40000000
#define SPI_FREQUENCY 55000000 // STM32 SPI1 only (SPI2 maximum is 27MHz)
//#define SPI_FREQUENCY 65000000
//#define SPI_FREQUENCY 80000000
// Optional reduced SPI frequency for reading TFT
#define SPI_READ_FREQUENCY 20000000
// The XPT2046 requires a lower SPI clock rate of 2.5MHz so we define that here:
#define SPI_TOUCH_FREQUENCY 2500000
// The ESP32 has 2 free SPI ports i.e. VSPI and HSPI, the VSPI is the default.
// If the VSPI port is in use and pins are not accessible (e.g. TTGO T-Beam)
// then uncomment the following line:
//#define USE_HSPI_PORT
// Comment out the following #define if "SPI Transactions" do not need to be
// supported. When commented out the code size will be smaller and sketches will
// run slightly faster, so leave it commented out unless you need it!
// Transaction support is needed to work with SD library but not needed with TFT_SdFat
// Transaction support is required if other SPI devices are connected.
// Transactions are automatically enabled by the library for an ESP32 (to use HAL mutex)
// so changing it here has no effect
// #define SUPPORT_TRANSACTIONS
the CYD has an onboard ESP32 microcontroller so minimal changes to add TFT display output (plus GPIO input pins updated)