Merge branch 'clock_jockey' of https://git.cuvoodoo.info/stm32f1 into clock_jockey

README.md

@@ -1,54 +1,97 @@
-This firmware template is designed for development boards based around [STM32 F1 series micro-controller](http://www.st.com/web/en/catalog/mmc/FM141/SC1169/SS1031).
-
 project
 =======
 
 summary
 -------
 
-*describe project purpose*
+this clock jockey monitors the tachometer of a motor turning a clock, and regulates its speed by switching the power to it.
 
 technology
 ----------
 
-*described electronic details*
+the goal was to make a round clock quadrant turn.
+the quadrant is made out of wood, around 1 m heigh, and weights around 5 kg.
+it is mounted on a disco ball base.
+the bearing is strong enough to hold it and allow the clock to turn around its center.
+
+originally the disco ball base included a motor, but it was too fragile to withhold the forces.
+two plastic gears in the gear box broke.
+this was the state of the clock when I joined the team.
+I decided to fix the turning clock.
+the small DC or stepper motor I tried were too weak to turn the clock.
+I decided to use a universal motor salvaged from a washing machine.
+
+the pinout of the motor was undocumented, but not hard to figure out.
+two wires went to a small module at the end of the rotor shaft.
+this is the tachometer to measure the rotation speed.
+it is also easy to trace the two wires going to the brushes feeding the power to the rotor coils.
+next, measure the resistance of the remaining pin pairs.
+one will have 0 Ohms.
+this is the fuse to protect against over-heating.
+there will be two pairs of 0.6 Ohms, and one of 1.2 Ohms.
+these are the two coils for the stator, with a center tap.
+
+wire the motor with 220V AC the following way:
+AC L - fuse - rotor - stator (2 coils, not center tap) - AC N
+to limit the speed I used a 4000 W capable SCR.
+the SCR was not enough to regulate the motor speed.
+setting the potentiometer to a fixed point would results in the motor to stop turning after some time, of to speed up to fast.
+the user would have to adjust the potentiometer using then knob periodically to have a somewhat constant speed.
+
+to overcome this limitation I developed the clock jockey.
+this device will monitor the speed of the motor using the tachometer, and switch the power to the motor using a Solid State Relay (SSR), so to reach and stay at the predefined speed.
+
+the motor tachometer provides an AC signal.
+basically it's a generating motor linked to the shaft of the actual motor.
+the AC frequency (and voltage) indicates the speed of the motor.
+the AC signal is rectified using a full bridge rectifier.
+the rectified signal is input to an PC817 optocoupler (with ~ 200 Ohm inline resistor).
+the full bridge rectifier protects to optocoupler, which has a reverse breakdown voltage of 6 V, lower than the seen -10 V peaks of the AC signal.
+it also allows to get two pulses per AC period, for a more accurate speed measurement.
+the optocoupler is directly connected to the clock jockey.
+an omron G3MB-202P (5V) is also connected to the clock jockey to switch to power going to the motor.
+the SCR is still in line to limit the maximum delivered power.
 
 board
 =====
 
-The current implementation uses a [core board](https://wiki.cuvoodoo.info/doku.php?id=stm32f1xx#core_board).
+the device reuses an [ST-LINK/V2 clone](https://wiki.cuvoodoo.info/doku.php?id=jtag#mini_st-link_v2).
+this board uses a STM32F103C8T6 micro-controller.
 
-The underlying template also supports following board:
-
-- [Maple Mini](http://leaflabs.com/docs/hardware/maple-mini.html), based on a STM32F103CBT6
-- [System Board](https://wiki.cuvoodoo.info/doku.php?id=stm32f1xx#system_board), based on a STM32F103C8T6
-- [blue pill](ihttps://wiki.cuvoodoo.info/doku.php?id=stm32f1xx#blue_pill), based on a STM32F103C8T6
-- [core board](https://wiki.cuvoodoo.info/doku.php?id=stm32f1xx#core_board), based on a STM32F103C8T6
-- [ST-LINK V2 mini](https://wiki.cuvoodoo.info/doku.php?id=jtag#mini_st-link_v2), a ST-LINK/V2 clone based on a STM32F101C8T6
-- [USB-Blaster](https://wiki.cuvoodoo.info/doku.php?id=jtag#armjishu_usb-blaster), an Altera USB-Blaster clone based on a STM32F101C8T6
-
-**Which board is used is defined in the Makefile**.
-This is required to map the user LED and button provided on the board
-
-The ST-LINK V2 mini clone has SWD test points on the board.
-Because read protection is enabled, you will first need to remove the protection to be able to flash the firmware.
-To remove the read protection (and erase flash), run `rake remove_protection` while a SWD adapter is connected.
-
-The Altera USB-Blaster clone has a pin header for SWD and UART1 on the board.
-SWD is disabled in the main firmware, and it has read protection.
-To be able to flash using SWD (or the serial port), the BOOT0 pin must be set to 1 to boot the system memory install of the flash memory.
-To set BOOT0 to 1, apply 3.3 V on R11, between the resistor and the reference designator, when powering the device.
-The red LED should stay off while the green LED is on.
-Now you can remove the read protection (and erase flash), run `rake remove_protection` while a SWD adapter is connected.
+since the device is firmware protected (against read-out), you will first need to remove this protection using an SWD adapter and running `rake remove_protection`.
+you can then flash the bootloader using SWD and application using DFU a documented in the section below.
 
 connections
 ===========
 
-Connect the peripherals the following way (STM32F10X signal; STM32F10X pin; peripheral pin; peripheral signal; comment):
+connect the peripherals the following way:
 
-- *list board to preipheral pin connections*
+- PC817X emitter, SWIM pin (PB11, pulled up to 3V3 on board)
+- PC817X collector, GND
+- G3MB-202P SSR 3+, 5V (5V required by SSR, with embedded resistor)
+- G3MB-202P SSR 4-, SWDIO (SWCLK pin in not 5V tolerant)
 
-All pins are configured using `define`s in the corresponding source code.
+all pins are configured using `define`s in the corresponding source code.
+
+usage
+=====
+
+the firmware will simply count the number of optocoupler falling edges (2 per revolution).
+it will periodically compare this count to the target value.
+if this is below, the SSR will be switched on.
+if it is above, the SSR will be switched off.
+
+to set this target, connect the clock jokey to a computer.
+it will appear as a serial device (using the CDC ACM USB profile).
+use a serial terminal program and connect to it (the baud rate does not matter).
+enter `tacho xx`, with xx being the target tachometer count.
+to view the set and current tachometer values, enter `tacho`.
+
+the target tachometer count is somewhat relative.
+it is proportional to the motor speed and tied to the periodic check (currently set to 0.1 s).
+
+if the tacho count it at 0 for too many seconds after boot, the clock jockey will with off the power.
+this is a safety feature since the tachometer is either not reading the speed, or the motor is stuck.
 
 code
 ====
@@ -86,7 +129,7 @@ The `Makefile` uses a Black Magic Probe (per default), or a ST-Link V2 along Ope
 To flash the `booltoader` using SWD run `rake flash_booloader`.
 
 Once the `bootloader` is flashed it is possible to flash the `application` over USB using the DFU protocol by running `rake flash`.
-To force the bootloader to start the DFU mode press the user button or short a pin, depending on the board.
+To force the bootloader to start the DFU mode, short the RST pin to the nearby ground pin.
 It is also possible to flash the `application` image using SWD by running `rake flash_application`.
 
 debug
@@ -98,8 +141,4 @@ To start the debugging session run `rake debug`.
 USB
 ---
 
-The firmware offers serial communication over USART1 and USB (using the CDC ACM device class).
-
-You can also reset the board by setting the serial width to 5 bits over USB.
-To reset the board run `rake reset`.
-This only works if provided USB CDC ACM is running correctly and the micro-controller isn't stuck.
+The firmware offers serial communication over USB (using the CDC ACM device class).

Rakefile

@@ -15,7 +15,7 @@ FIRMWARES = [BOOTLOADER, APPLICATION]
 
 # which development board is used
 # supported are: SYSTEM_BOARD, MAPLE_MINI, BLUE_PILL, CORE_BOARD, STLINKV2, BLASTER, BUSVOODOO
-BOARD = ENV["BOARD"] || "CORE_BOARD"
+BOARD = ENV["BOARD"] || "STLINKV2"
 
 # libopencm3 definitions
 LIBOPENCM3_DIR = "libopencm3"

application.c

@@ -15,7 +15,7 @@
 /** STM32F1 application example
  *  @file application.c
  *  @author King Kévin <kingkevin@cuvoodoo.info>
- *  @date 2016-2019
+ *  @date 2016-2020
  */
 
 /* standard libraries */
@@ -37,6 +37,7 @@
 #include <libopencm3/stm32/dbgmcu.h> // debug utilities
 #include <libopencm3/stm32/desig.h> // design utilities
 #include <libopencm3/stm32/flash.h> // flash utilities
+#include <libopencm3/stm32/timer.h> // timer utilities
 
 /* own libraries */
 #include "global.h" // board definitions
@@ -47,12 +48,16 @@
 #include "usb_cdcacm.h" // USB CDC ACM utilities
 #include "terminal.h" // handle the terminal interface
 #include "menu.h" // menu utilities
+#include "flash_internal.h" // menu utilities
 
-#define WATCHDOG_PERIOD 10000 /**< watchdog period in ms */
+#define WATCHDOG_PERIOD 3000 /**< watchdog period in ms */
 /** set to 0 if the RTC is reset when the board is powered on, only indicates the uptime
  *  set to 1 if VBAT can keep the RTC running when the board is unpowered, indicating the date and time
  */
-#define RTC_DATE_TIME 1
+#define RTC_DATE_TIME 0
+
+/** number of RTC ticks per second */
+#define RTC_TICKS 10
 
 /** RTC time when device is started */
 static time_t time_start = 0;
@@ -63,6 +68,13 @@ static time_t time_start = 0;
 volatile bool rtc_internal_tick_flag = false; /**< flag set when internal RTC ticked */
 /** @} */
 
+volatile uint32_t tacho_count = 0; /**< tachometer edge count */
+bool tacho_display = false; /**< if the current tachometer count should be displayed */
+#define TACHO_PIN PB11 /**< tachometer input on SWIM pin, pulled up to 3V3 by 680R */
+#define TACHO_TARGET_DEFAULT 20 /**< the default target tachometer count (slow for safety) */
+uint32_t tacho_target = TACHO_TARGET_DEFAULT; /**< the target tachometer count (switch SSR on when below, off when above) */
+#define SSR_PIN PB14 /**< pin to control the SSR (SWDIO, active low, open drain to 5V) */
+
 size_t putc(char c)
 {
 	size_t length = 0; // number of characters printed
@@ -117,6 +129,30 @@ static void command_reset(void* argument);
  */
 static void command_bootloader(void* argument);
 
+static void command_tacho(void* argument)
+{
+	(void)argument; // we won't use the argument
+
+	if (argument) { // tachometer value has been provided
+		uint32_t target = *(uint32_t*)argument; // get target tachometer value
+		printf("setting target tachometer value to %u\n", target);
+		tacho_target = target;
+		// save to EEPROM
+		const uint32_t eeprom_tacho[2] = {tacho_target, tacho_target ^ 0xffffffff};
+		const int32_t rc = flash_internal_eeprom_write((uint8_t*)eeprom_tacho, sizeof(eeprom_tacho));
+		if (rc != sizeof(eeprom_tacho)) {
+			printf("could not save value to EEPROM: %d\n", rc);
+		}
+	} else {
+		if (tacho_display) {
+			tacho_display = false;
+		} else {
+			printf("target tachometer value set to %u\n", tacho_target);
+			tacho_display = true;
+		}
+	}
+}
+
 /** list of all supported commands */
 static const struct menu_command_t menu_commands[] = {
 	{
@@ -169,6 +205,14 @@ static const struct menu_command_t menu_commands[] = {
 		.argument_description = NULL,
 		.command_handler = &command_bootloader,
 	},
+	{
+		.shortcut = 't',
+		.name = "tacho",
+		.command_description = "set/show/hide tachometer target and current value",
+		.argument = MENU_ARGUMENT_UNSIGNED,
+		.argument_description = "[target]",
+		.command_handler = &command_tacho,
+	},
 };
 
 static void command_help(void* argument)
@@ -330,7 +374,7 @@ void main(void)
 	uart_setup(); // setup USART (for printing)
 #endif
 	usb_cdcacm_setup(); // setup USB CDC ACM (for printing)
-	puts("\nwelcome to the CuVoodoo STM32F1 example application\n"); // print welcome message
+	puts("\nwelcome to the CuVoodoo dachboden clock turner\n"); // print welcome message
 
 #if DEBUG
 	// show reset cause
@@ -374,7 +418,7 @@ void main(void)
 	printf("setup internal RTC: ");
 #if defined(BLUE_PILL) || defined(STLINKV2) || defined(BLASTER) // for boards without a Low Speed External oscillator
 	// note: the blue pill LSE oscillator is affected when toggling the onboard LED, thus prefer the HSE
-	rtc_auto_awake(RCC_HSE, 8000000 / 128 - 1); // use High Speed External oscillator (8 MHz / 128) as RTC clock (VBAT can't be used to keep the RTC running)
+	rtc_auto_awake(RCC_HSE, 8000000 / 128 / RTC_TICKS - 1); // use High Speed External oscillator (8 MHz / 128) as RTC clock (VBAT can't be used to keep the RTC running)
 #else // for boards with an precise Low Speed External oscillator
 	rtc_auto_awake(RCC_LSE, 32768 - 1); // ensure internal RTC is on, uses the 32.678 kHz LSE, and the prescale is set to our tick speed, else update backup registers accordingly (power off the micro-controller for the change to take effect)
 #endif
@@ -383,6 +427,40 @@ void main(void)
 	time_start = rtc_get_counter_val(); // get start time from internal RTC
 	printf("OK\n");
 
+	printf("setup SSR: ");
+	rcc_periph_clock_enable(GPIO_RCC(SSR_PIN)); // enable clock for GPIO peripheral
+	gpio_set(GPIO_PORT(SSR_PIN), GPIO_PIN(SSR_PIN)); // set high to switch off
+	gpio_set_mode(GPIO_PORT(SSR_PIN), GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO_PIN(SSR_PIN)); // set SSR - control pin to open drain. active low, connected to 5V on the + pin
+	printf("OK\n");
+	
+	// setup timer to measure motor tachometer
+	printf("setup tachometer measurer: ");
+	rcc_periph_clock_enable(GPIO_RCC(TACHO_PIN)); // enable clock for GPIO peripheral
+	gpio_set_mode(GPIO_PORT(TACHO_PIN), GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN, GPIO_PIN(TACHO_PIN)); // set tachometer pin to input
+	rcc_periph_clock_enable(RCC_AFIO); // enable alternate function clock for external interrupt
+	exti_select_source(GPIO_EXTI(TACHO_PIN), GPIO_PORT(TACHO_PIN)); // mask external interrupt of this pin only for this port
+	gpio_set(GPIO_PORT(TACHO_PIN), GPIO_PIN(TACHO_PIN)); // pull up to eliminate noise
+	exti_set_trigger(GPIO_EXTI(TACHO_PIN), EXTI_TRIGGER_FALLING); // trigger when opto-coupler triggers
+	exti_enable_request(GPIO_EXTI(TACHO_PIN)); // enable external interrupt
+	nvic_enable_irq(GPIO_NVIC_EXTI_IRQ(TACHO_PIN)); // enable interrupt
+	printf("OK\n");
+
+	// load target tachometer value from EEPROM
+	uint32_t eeprom_tacho[2];
+	flash_internal_eeprom_setup(1); // use 1 page for EEPROM emulation
+	bool eeprom_read = flash_internal_eeprom_read((uint8_t*)eeprom_tacho, sizeof(eeprom_tacho));
+	printf("target tachometer count (");
+	if (eeprom_read && eeprom_tacho[0] == (eeprom_tacho[1] ^ 0xffffffff)) {
+		tacho_target = eeprom_tacho[0];
+		printf("set");
+	} else {
+		tacho_target = TACHO_TARGET_DEFAULT;
+		printf("default");
+	}
+	bool tacho_safety = false; // if the motor is switched of for safety reasons
+	uint32_t tacho_activity = rtc_get_counter_val(); // when was the last time we saw the motor spinning
+	printf("): %u\n", tacho_target);
+
 	// setup terminal
 	terminal_prefix = ""; // set default prefix
 	terminal_process = &process_command; // set central function to process commands
@@ -390,7 +468,6 @@ void main(void)
 
 	// start main loop
 	bool action = false; // if an action has been performed don't go to sleep
-	button_flag = false; // reset button flag
 	while (true) { // infinite loop
 		iwdg_reset(); // kick the dog
 		if (user_input_available) { // user input is available
@@ -399,19 +476,32 @@ void main(void)
 			char c = user_input_get(); // store receive character
 			terminal_send(c); // send received character to terminal
 		}
-		if (button_flag) { // user pressed button
-			action = true; // action has been performed
-			printf("button pressed\n");
-			led_toggle(); // toggle LED
-			for (uint32_t i = 0; i < 1000000; i++) { // wait a bit to remove noise and double trigger
-				__asm__("nop");
-			}
-			button_flag = false; // reset flag
-		}
 		if (rtc_internal_tick_flag) { // the internal RTC ticked
 			rtc_internal_tick_flag = false; // reset flag
 			action = true; // action has been performed
+			uint32_t tacho = tacho_count; // backup before clearing
+			tacho_count = 0; // restart count
 			led_toggle(); // toggle LED (good to indicate if main function is stuck)
+			if (!tacho_safety) {
+				if (tacho < tacho_target) {
+					 gpio_clear(GPIO_PORT(SSR_PIN), GPIO_PIN(SSR_PIN)); // switch SSR on to provide power
+				} else {
+					 gpio_set(GPIO_PORT(SSR_PIN), GPIO_PIN(SSR_PIN)); // switch SSR off to cut power
+				}
+				if (tacho) { // we tachometer indicates the motor is spinning
+					tacho_activity = rtc_get_counter_val(); // updated the last time we saw it spinning
+				} else if (rtc_get_counter_val() > tacho_activity + 5 * RTC_TICKS) { // the motor does not seem to turn, after 5 s
+					tacho_safety = true; // turn safety on
+					gpio_set(GPIO_PORT(SSR_PIN), GPIO_PIN(SSR_PIN)); // switch SSR off to cut power
+					printf("\ntachometer does not indicate the motor is turning\n");
+					printf("either the tachometer is defective, or the motor is stuck\n");
+					printf("switching the motor off for safety\n");
+					printf("reboot to retry\n");
+				}
+			}
+			if (tacho_display) {
+				printf("%u\n", tacho); // display tachometer frequency
+			}
 		}
 		if (action) { // go to sleep if nothing had to be done, else recheck for activity
 			action = false;
@@ -427,3 +517,10 @@ void rtc_isr(void)
 	rtc_clear_flag(RTC_SEC); // clear flag
 	rtc_internal_tick_flag = true; // notify to show new time
 }
+
+/** interrupt service routine called when tachometer edge is detected is pressed */
+void GPIO_EXTI_ISR(TACHO_PIN)(void)
+{
+	exti_reset_request(GPIO_EXTI(TACHO_PIN)); // reset interrupt
+	tacho_count++; // increment edge count
+}

bootloader.ld

@@ -23,6 +23,7 @@ PROVIDE(__flash_end = ORIGIN(rom) + LENGTH(rom));
 */
 PROVIDE(__application_end = 0);
 PROVIDE(__flash_end = 0);
+
 /* RAM location reserved so application can talk to bootloader and tell to start DFU */
 PROVIDE(__dfu_magic = ORIGIN(ram) - 4);
 

global.h

@@ -665,6 +665,9 @@
 #elif defined (BLASTER)
 	#define DFU_FORCE_PIN PA8 /**< GPIO pin (pin PA8, not SWD and UART pin on debug port) */
 	#define DFU_FORCE_VALUE 0 /**< short to nearby ground connection to force DFU */
+#elif defined(STLINKV2)
+	#define DFU_FORCE_PIN PB6 /**< RST pin pin */
+	#define DFU_FORCE_VALUE 0 /**< short to nearby GND pin to force DFU */
 #elif defined(BUSVOODOO)
 #if BUSVOODOO_HARDWARE_VERSION==0
 	/* on BusVoodoo v0 DFU input is on PC7 */

lib/usb_cdcacm.c

@@ -242,7 +242,7 @@ static char usb_serial[] = "00112233445566778899aabb";
  */
 static const char* usb_strings[] = {
 	"CuVoodoo", /**< manufacturer string */
-	"CuVoodoo STM32F1xx firmware", /**< product string */
+	"CuVoodoo dachboden clock jockey", /**< product string */
 	(const char*)usb_serial, /**< device ID used as serial number */
 	"DFU bootloader (runtime mode)", /**< DFU interface string */
 };