First Commit
Dependencies: mbed Crypto_light mbed-rtos
Spin it 2 win it
main.cpp
- Committer:
- henryeshbaugh
- Date:
- 2018-03-23
- Revision:
- 29:e28682c4b4cb
- Parent:
- 28:8076013fbef5
File content as of revision 29:e28682c4b4cb:
#include "mbed.h" #include "Crypto_light/hash/SHA256.h" #include "mbed-rtos/rtos/rtos.h" /* Photointerruptor input pins */ #define I1pin D2 #define I2pin D11 #define I3pin D12 /* Incremental encoder input pins */ #define CHA D7 #define CHB D8 /* Motor Drive output pins Mask in output byte */ #define L1Lpin D4 /* 0x01 */ #define L1Hpin D5 /* 0x02 */ #define L2Lpin D3 /* 0x04 */ #define L2Hpin D6 /* 0x08 */ #define L3Lpin D9 /* 0x10 */ #define L3Hpin D10 /* 0x20 */ /* max input length */ #define CHAR_ARR_SIZE 18 /* pwm/motor control definitions */ #define MAX_PWM_PERIOD 2000 #define MAX_TORQUE 1000 #define KP 20 #define KD 20 /* function-like macros for utility */ #define sgn(x) ((x)/abs(x)) #define max(x,y) ((x)>=(y)?(x):(y)) #define min(x,y) ((x)>=(y)?(y):(x)) #ifdef __GNUC__ #define likely(x) __builtin_expect((x), 1) #define unlikely(x) __builtin_expect((x), 0) #else #define likely(x) (x) #define unlikely(x) (x) #endif enum MSG {MSG_RESET, MSG_HASHCOUNT, MSG_NONCE_OK, MSG_OVERFLOW, MSG_ROT_PEN, MSG_MAX_SPD, MSG_NEW_KEY, MSG_INP_ERR, MSG_TORQUE, MSG_TEST, MSG_CUR_SPD, MSG_POS, MSG_NEW_VEL, MSG_NEW_ROTOR_POS}; /* Instantiate the serial port */ RawSerial pc(SERIAL_TX, SERIAL_RX); /* Status LED */ DigitalOut led1(LED1); /* Photointerrupter inputs */ InterruptIn I1(I1pin); InterruptIn I2(I2pin); InterruptIn I3(I3pin); /* motor drive outputs */ PwmOut L1L(L1Lpin); PwmOut L2L(L2Lpin); PwmOut L3L(L3Lpin); DigitalOut L1H(L1Hpin); DigitalOut L2H(L2Hpin); DigitalOut L3H(L3Hpin); /* givens from coursework handouts - motor states etc */ const int8_t drive_table[] = {0x12,0x18,0x09,0x21,0x24,0x06,0x00,0x00}; const int8_t state_map[] = {0x07,0x05,0x03,0x04,0x01,0x00,0x02,0x07}; volatile int8_t lead = 2, /* phase lead, -2 for backwards, 2 for forwards */ origin_state = 0; /* threads for serial I/O and motor control */ Thread comms_out_thrd(osPriorityLow, 1024); Thread comms_in_thrd(osPriorityLow, 1024); Thread motor_ctrl_thrd(osPriorityNormal, 2048); /* IPC via Mail object; we instantiate here */ typedef struct { char *stub; uint8_t code; int32_t data; } message_t; Mail<message_t, 16> msg_out_queue; /* bools are 8 bits and so access is atomic */ volatile bool key_updated = false, spin_forever = false; /* instantiate a queue to buffer incoming characters */ Queue<void, 8> serial_in_queue; /* motor control global variables */ volatile int32_t motor_position = 0, target_speed = 256, torque = 1000; volatile float rotations_pending = 0; volatile uint16_t hashcount = 0; /* hash count, reset every second when printed */ volatile uint64_t new_key = 0; /* used when selecting a new hash key */ /* logging function & shim macro for stringifying enum */ #define put_message(code, data) put_message_(#code, code, data) void put_message_(char *, uint8_t, int32_t); void comms_out_fn(void); /* serial output thread main */ void comms_in_fn(void); /* serial input thread main */ void serial_isr(void); /* serial event ISR */ void photointerrupter_isr(void); /* motor state change ISR */ void motor_ctrl_fn(void); /* motor control thread main */ void motor_ctrl_timer_isr(void); /* poke motor_ctrl at 100ms intervals */ void parse_serial_in(char *); /* interpret serial command */ void do_hashcount(void); /* print current hash count */ inline int8_t read_rotor_state(void); /* get rotor position */ int8_t motor_home(void); /* establish motor origin position */ void motor_out(int8_t, uint32_t); /* do motor output */ int main(void) { comms_out_thrd.start(&comms_out_fn); motor_ctrl_thrd.start(&motor_ctrl_fn); comms_in_thrd.start(&comms_in_fn); put_message(MSG_RESET, 0); /* sync motor to home */ rotations_pending = origin_state = motor_home(); /* register ISRs */ I1.rise(&photointerrupter_isr); I2.rise(&photointerrupter_isr); I3.rise(&photointerrupter_isr); I1.fall(&photointerrupter_isr); I2.fall(&photointerrupter_isr); I3.fall(&photointerrupter_isr); /* set PWM period */ L1L.period_us(MAX_PWM_PERIOD); L2L.period_us(MAX_PWM_PERIOD); L3L.period_us(MAX_PWM_PERIOD); /* Calling the ISR once starts the motor movement */ photointerrupter_isr(); /* SHA256-related data */ SHA256 sha256; uint8_t sequence[] = {0x45,0x6D,0x62,0x65,0x64,0x64,0x65,0x64, 0x20,0x53,0x79,0x73,0x74,0x65,0x6D,0x73, 0x20,0x61,0x72,0x65,0x20,0x66,0x75,0x6E, 0x20,0x61,0x6E,0x64,0x20,0x64,0x6F,0x20, 0x61,0x77,0x65,0x73,0x6F,0x6D,0x65,0x20, 0x74,0x68,0x69,0x6E,0x67,0x73,0x21,0x20, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}; uint64_t *key = (uint64_t*)((int)sequence + 48); uint64_t *nonce = (uint64_t*)((int)sequence + 56); uint8_t hash[32]; Ticker hashcounter; hashcounter.attach(&do_hashcount, 1.0); while (1) { /* compute new hash - let gcc know this is not likely */ if (unlikely(key_updated)) { /* no serialization is needed here; a new serial key * * command needs 18 bytes over serial (15ms) - we * * run at least 8k hashes per second, meaning this * * condition is hit roughly every 125us. Even if two * * key change commands were sent at once, we wouldn't * * hit a race condition. The worry is we get * * scheduled out in favor of serial in halfway * * through writing the new key (64 bits) specifically * * to get a new key from a user command, but that * * /can't/ happen because of the serial latency. */ *key = new_key; key_updated = false; } /* compute the hash */ sha256.computeHash(hash, sequence, 64); if (hash[0] == 0 && hash[1] == 0) put_message(MSG_NONCE_OK, *nonce); (*nonce)++; hashcount++; } } void put_message_(char *str, uint8_t code, int32_t data) { message_t *message = msg_out_queue.alloc(); message->code = code; message->data = data; message->stub = str; msg_out_queue.put(message); } void comms_out_fn() { while(1) { osEvent new_event = msg_out_queue.get(); message_t *message = (message_t*) new_event.value.p; pc.printf("[%d:%16s], data: %010d\r\n", message->code, message->stub, message->data); msg_out_queue.free(message); } } /* serial port ISR to receive each incoming byte and place into queue */ void serial_isr() { uint8_t new_char = pc.getc(); serial_in_queue.put((void*) new_char); } /* photointerrupter ISR drives the motors */ void photointerrupter_isr() { static int8_t old_rotor_state = 0; int8_t rotor_state = read_rotor_state(); motor_out((rotor_state-origin_state+lead+6)%6, torque); /* +6 to make sure the remainder is positive */ if (rotor_state - old_rotor_state == 5) motor_position--; else if (rotor_state - old_rotor_state == -5) motor_position++; else motor_position += (rotor_state - old_rotor_state); old_rotor_state = rotor_state; } /* motor control thread sets a timer ISR, this is the handler */ void motor_ctrl_timer_isr() { motor_ctrl_thrd.signal_set(0x1); } /* motor control thread main */ void motor_ctrl_fn() { Ticker motor_control_ticker; Timer timer; uint8_t count = 0; int32_t cur_pos = 0, old_pos = 0, cur_speed, ys, yr; uint32_t cur_time = 0, old_time = 0, time_diff; float cur_err = 0.0f, old_err = 0.0f, err_diff; motor_control_ticker.attach_us(&motor_ctrl_timer_isr,100000); timer.start(); while(1) { /* wait for the 100ms boundary */ motor_ctrl_thrd.signal_wait(0x1); /* read state & timestamp */ cur_time = timer.read(); cur_pos = motor_position; /* compute speed */ time_diff = cur_time - old_time; cur_speed = (cur_pos - old_pos) / time_diff; /* prep values for next time through loop */ old_time = cur_time; old_pos = cur_pos; count = ++count % 10; /* update with motor status */ /* * if (!count) { * put_message(MSG_CUR_SPD, cur_speed); * put_message(MSG_MAX_SPD, target_speed); * put_message(MSG_POS, (cur_pos/6)); * put_message(MSG_ROT_PEN, rotations_pending); * put_message(MSG_TORQUE, torque); * } */ /* compute position error */ cur_err = rotations_pending - (cur_pos/6.0f); err_diff = cur_err - old_err; old_err = cur_err; /* compute torques */ ys = (int32_t) (20 * (target_speed - abs(cur_speed))) * sgn(cur_err); /* select minimum absolute value torque, or just take ys and spin forever */ if (likely(!spin_forever)) { yr = (int32_t) ((20 * cur_err) + (40 * err_diff)); if (cur_speed < 0) torque = max(ys, yr); else torque = min(ys, yr); } else torque = ys; /* fix torque if negative */ if (torque < 0) torque = -torque, /* <- comma operator in action */ lead = -2; else lead = 2; /* cap torque */ if (torque > MAX_TORQUE) torque = MAX_TORQUE; /* finally, give the motor a kick */ photointerrupter_isr(); } } /* parse input with sscanf() */ void parse_serial_in(char *s) { /* shadow output variables so writes are guaranteed atomic */ uint64_t new_key_; int32_t torque_; int32_t target_speed_; float rotations_pending_; if (sscanf(s, "R%f", &rotations_pending_)) { rotations_pending += rotations_pending_; if (rotations_pending_ == 0.0f) spin_forever = true; else spin_forever = false; /* put_message(MSG_ROT_PEN, rotations_pending); */ } else if (sscanf(s, "V%d", &target_speed_)) { target_speed = target_speed_; /* put_message(MSG_NEW_VEL, target_speed); */ } else if (sscanf(s, "K%llx", &new_key_)) { new_key = new_key_; key_updated = true; /* put_message(MSG_NEW_KEY, new_key); */ } else if (sscanf(s, "T%u", &torque_)) { torque = torque_; photointerrupter_isr(); //Give it a kick /* put_message(MSG_TORQUE, torque); */ } else put_message(MSG_INP_ERR, 0x404); } void comms_in_fn() { /* register serial interrupt handler */ pc.attach(&serial_isr); char char_seq[CHAR_ARR_SIZE] = ""; uint8_t buf_pos = 0; while (1) { if (buf_pos >= CHAR_ARR_SIZE) { put_message(MSG_OVERFLOW, buf_pos); buf_pos = 0; } else { osEvent new_event = serial_in_queue.get(); uint8_t new_char = (uint8_t)new_event.value.p; if (new_char == '\r' || new_char == '\n') { char_seq[buf_pos] = '\0'; buf_pos = 0; parse_serial_in(char_seq); } else char_seq[buf_pos++] = new_char; } } } /* timer ISR to print/reset hash counts every second */ void do_hashcount() { put_message(MSG_HASHCOUNT, hashcount); hashcount = 0; } /* Set a given drive state */ void motor_out(int8_t driveState, uint32_t t){ /* Lookup the output byte from the drive state. */ int8_t driveOut = drive_table[driveState & 0x07]; /* Turn off first */ if (~driveOut & 0x01) L1L.pulsewidth_us(0); if (~driveOut & 0x02) L1H = 1; if (~driveOut & 0x04) L2L.pulsewidth_us(0); if (~driveOut & 0x08) L2H = 1; if (~driveOut & 0x10) L3L.pulsewidth_us(0); if (~driveOut & 0x20) L3H = 1; /* Then turn on */ if (driveOut & 0x01) L1L.pulsewidth_us(t); if (driveOut & 0x02) L1H = 0; if (driveOut & 0x04) L2L.pulsewidth_us(t); if (driveOut & 0x08) L2H = 0; if (driveOut & 0x10) L3L.pulsewidth_us(t); if (driveOut & 0x20) L3H = 0; } /* Convert photointerrupter inputs to a rotor state */ inline int8_t read_rotor_state() { return state_map[I1 + 2*I2 + 4*I3]; } /* Basic synchronisation routine */ int8_t motor_home() { /* Put the motor in drive state 0 and wait for it to stabilise */ motor_out(0, MAX_TORQUE); wait(2.0); /* Get the rotor state */ return read_rotor_state(); } /* hank rulez */