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-rw-r--r--fw/main.c681
1 files changed, 25 insertions, 656 deletions
diff --git a/fw/main.c b/fw/main.c
index 7740426..c0ad092 100644
--- a/fw/main.c
+++ b/fw/main.c
@@ -1,624 +1,30 @@
-/* Workaround for sub-par ST libraries */
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wstrict-aliasing"
-#include <stm32f0xx.h>
-#include <stm32f0xx_ll_utils.h>
-#include <stm32f0xx_ll_spi.h>
-#pragma GCC diagnostic pop
-
-#include <system_stm32f0xx.h>
-
-#include <stdint.h>
-#include <stdbool.h>
-#include <string.h>
-#include <unistd.h>
-
-#include "transpose.h"
-#include "mac.h"
-
-/* Microcontroller part number: STM32F030F4C6 */
-
-/* Things used for module status reporting. */
-#define FIRMWARE_VERSION 2
-#define HARDWARE_VERSION 4
-
-#define TS_CAL1 (*(uint16_t *)0x1FFFF7B8)
-#define VREFINT_CAL (*(uint16_t *)0x1FFFF7BA)
+/* Megumin LED display firmware
+ * Copyright (C) 2018 Sebastian Götte <code@jaseg.net>
+ *
+ * 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 3 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/>.
+ */
-volatile int16_t adc_vcc_mv = 0;
-volatile int16_t adc_temp_celsius = 0;
+#include "global.h"
-volatile uint16_t adc_buf[2];
+#include "display.h"
+#include "serial.h"
+#include "led.h"
+#include "adc.h"
volatile unsigned int sys_time = 0;
volatile unsigned int sys_time_seconds = 0;
-/* Error counters for debugging */
-static unsigned int uart_overruns = 0;
-static unsigned int frame_overruns = 0;
-static unsigned int invalid_frames = 0;
-
-/* Status LED control */
-#define LED_STRETCHING_MS 50
-static volatile int error_led_timeout = 0;
-static volatile int comm_led_timeout = 0;
-static volatile int id_led_timeout = 0;
-
-/* Modulation data */
-volatile struct framebuf fb[2] = {0};
-volatile struct framebuf *read_fb=fb+0, *write_fb=fb+1;
-volatile int led_state = 0;
-volatile enum { FB_WRITE, FB_FORMAT, FB_UPDATE } fb_op;
-volatile union {
- struct __attribute__((packed)) { struct framebuf fb; uint8_t end[0]; } set_fb_rq;
- struct __attribute__((packed)) { uint8_t nbits; uint8_t end[0]; } set_nbits_rq;
- uint8_t byte_data[0];
- uint32_t mac_data;
-} rx_buf;
-
-/* Auxiliary shift register values */
-#define LED_COMM 0x0001
-#define LED_ERROR 0x0002
-#define LED_ID 0x0004
-#define SR_ILED_HIGH 0x0080
-#define SR_ILED_LOW 0x0040
-
-/* This is a lookup table mapping segments to present a standard segment order on the UART interface. This is converted
- * into an internal representation once on startup in main(). The data type must be at least uint16. */
-uint32_t segment_map[8] = {5, 7, 6, 4, 1, 3, 0, 2};
-
-static volatile int frame_duration_us;
-volatile int nbits = MAX_BITS;
-
-static unsigned int active_bit = 0;
-static int active_segment = 0;
-
-/* Bit timing base value. This is the lowes bit interval used in TIM1/TIM3 timer counts. */
-#define PERIOD_BASE 4
-
-/* This value is a constant offset added to every bit period to allow for the timer IRQ handler to execute. This is set
- * empirically using a debugger and a logic analyzer.
- *
- * This value is in TIM1/TIM3 timer counts. */
-#define TIMER_CYCLES_FOR_SPI_TRANSMISSIONS 9
-
-/* This value sets the point when the LED strobe is asserted after the begin of the current bit cycle and IRQ
- * processing. This must be less than TIMER_CYCLES_FOR_SPI_TRANSMISSIONS but must be large enough to allow for the SPI
- * transmission to reliably finish.
- *
- * This value is in TIM1/TIM3 timer counts. */
-#define TIMER_CYCLES_BEFORE_LED_STROBE 8
-
-/* This value sets how long the TIM1 CC IRQ used for AUX register setting etc. is triggered before the end of the
- * longest cycle. This value should not be larger than PERIOD_BASE<<MIN_BITS to make sure the TIM1 CC IRQ does only
- * trigger in the longest cycle no matter what nbits is set to.
- *
- * This value is in TIM1/TIM3 timer counts. */
-#define AUX_SPI_PRETRIGGER 64 /* trigger with about 24us margin to the end of cycle/next TIM3 IRQ */
-
-/* This value sets how long a batch of ADC conversions used for temperature measurement is started before the end of the
- * longest cycle. Here too the above caveats apply.
- *
- * This value is in TIM1/TIM3 timer counts. */
-#define ADC_PRETRIGGER 150 /* trigger with about 12us margin to TIM1 CC IRQ */
-
-/* Defines for brevity */
-#define A TIMER_CYCLES_FOR_SPI_TRANSMISSIONS
-#define B PERIOD_BASE
-
-/* This is a constant offset containing some empirically determined correction values */
-#define C (0)
-
-/* This lookup table maps bit positions to timer period values. This is a lookup table to allow for the compensation for
- * non-linear effects of ringing at lower bit durations.
- */
-static uint16_t timer_period_lookup[MAX_BITS+1] = {
- /* LSB here */
- A - C + (B<< 0),
- A - C + (B<< 1),
- A - C + (B<< 2),
- A - C + (B<< 3),
- A - C + (B<< 4),
- A - C + (B<< 5),
- A - C + (B<< 6),
- A - C + (B<< 7),
- A - C + (B<< 8),
- A - C + (B<< 9),
- A - C + (B<< 0),
- /* MSB here */
-};
-
-/* Don't pollute the global namespace */
-#undef A
-#undef B
-#undef C
-
-void cfg_timers_led() {
- /* Ok, so this part is unfortunately a bit involved.
- *
- * Because the GPIO alternate function assignments worked out that way, the LED driving logic uses timers 1 and 3.
- * Timer 1 is synchronized to timer 3. When timer 3 overflows, timer 1 is reset. Both use the same prescaler so both
- * are synchronous possibly modulo some propagation delay in the synchronization hardware.
- *
- * Timer 3:
- * * The IRQ handler is set to trigger on overflow and
- * * triggers the SPI transmissions to the LED drivers and
- * * updates the timing logic with the delays for the next cycle
- * * Compare unit 1 generates the !OE signal for the led drivers
- * Timer 1:
- * * Compare unit 1 triggers the interrupt handler only in the longest bit cycle. The IRQ handler
- * * transmits the data to the auxiliary shift registers and
- * * swaps the frame buffers if pending
- * * Compare unit 2 generates the led drivers' STROBE signal
- *
- * The AUX_STROBE signal for the two auxiliary shift registers that deal with segment selection, current setting and
- * status leds is generated in software in both ISRs. TIM3's ISR indiscriminately resets this strobe every bit
- * cycle, and TIM1's ISR sets it every NBITSth bit cycle.
- *
- * The reason both timers' IRQ handlers are used is that this way no big if/else statement is necessary to
- * distinguish between both cases. Timer 1's IRQ handler is set via CC2 to trigger a few cycles earlier than the end
- * of the longest bit cycle. This means that if both timers perform bit cycles of length 1, 2, 4, 8, 16 and 32
- * TIM1_CC2 will be set to trigger at count e.g. 28. This means it is only triggered once in the last timer cycle.
- */
-
- TIM3->CR2 = (2<<TIM_CR2_MMS_Pos); /* master mode: update */
- TIM3->CCMR1 = (6<<TIM_CCMR1_OC1M_Pos) | TIM_CCMR1_OC1PE; /* PWM Mode 1, enable CCR preload */
- TIM3->CCER = TIM_CCER_CC1E;
- TIM3->CCR1 = TIMER_CYCLES_FOR_SPI_TRANSMISSIONS;
- TIM3->DIER = TIM_DIER_UIE;
- TIM3->PSC = SystemCoreClock/5000000 * 2 - 1; /* 0.20us/tick */
- TIM3->ARR = 0xffff;
- TIM3->EGR |= TIM_EGR_UG;
- TIM3->CR1 = TIM_CR1_ARPE;
- TIM3->CR1 |= TIM_CR1_CEN;
-
- /* Slave TIM1 to TIM3. */
- TIM1->PSC = TIM3->PSC;
- TIM1->SMCR = (2<<TIM_SMCR_TS_Pos) | (4<<TIM_SMCR_SMS_Pos); /* Internal Trigger 2 (ITR2) -> TIM3; slave mode: reset */
-
- /* Setup CC1 and CC2. CC2 generates the LED drivers' STROBE, CC1 triggers the IRQ handler */
- TIM1->BDTR = TIM_BDTR_MOE;
- TIM1->CCMR1 = (6<<TIM_CCMR1_OC2M_Pos) | TIM_CCMR1_OC2PE; /* PWM Mode 1, enable CCR preload for AUX_STROBE */
- TIM1->CCMR2 = (6<<TIM_CCMR2_OC4M_Pos); /* PWM Mode 1 */
- TIM1->CCER = TIM_CCER_CC1E | TIM_CCER_CC2E | TIM_CCER_CC4E;
- TIM1->CCR2 = TIMER_CYCLES_BEFORE_LED_STROBE;
- /* Trigger at the end of the longest bit cycle. This means this does not trigger in shorter bit cycles. */
- TIM1->CCR1 = timer_period_lookup[nbits-1] - AUX_SPI_PRETRIGGER;
- TIM1->CCR4 = timer_period_lookup[nbits-1] - ADC_PRETRIGGER;
- TIM1->DIER = TIM_DIER_CC1IE;
-
- TIM1->ARR = 0xffff; /* This is as large as possible since TIM1 is reset by TIM3. */
- /* Preload all values */
- TIM1->EGR |= TIM_EGR_UG;
- TIM1->CR1 = TIM_CR1_ARPE;
- /* And... go! */
- TIM1->CR1 |= TIM_CR1_CEN;
-
- /* Sends aux data and swaps frame buffers if necessary */
- NVIC_EnableIRQ(TIM1_CC_IRQn);
- NVIC_SetPriority(TIM1_CC_IRQn, 0);
- /* Sends LED data and sets up the next bit cycle's timings */
- NVIC_EnableIRQ(TIM3_IRQn);
- NVIC_SetPriority(TIM3_IRQn, 0);
-}
-
-void TIM1_CC_IRQHandler() {
- //static int last_frame_time = 0;
- /* This handler takes about 1.5us */
- GPIOA->BSRR = GPIO_BSRR_BS_0; // Debug
-
- /* Set SPI baudrate to 12.5MBd for slow-ish 74HC(T)595. This is reset again in TIM3's IRQ handler.*/
- SPI1->CR1 |= (2<<SPI_CR1_BR_Pos);
-
- /* Advance bit counts and perform pending frame buffer swap */
- active_bit = 0;
- active_segment++;
- if (active_segment == NSEGMENTS) {
- active_segment = 0;
-
- /* Frame buffer swap */
- if (fb_op == FB_UPDATE) {
- volatile struct framebuf *tmp = read_fb;
- read_fb = write_fb;
- write_fb = tmp;
- fb_op = FB_WRITE;
- }
- }
-
- /* Reset aux strobe */
- GPIOA->BSRR = GPIO_BSRR_BR_10;
- /* Send AUX register data */
- uint32_t aux_reg = (read_fb->brightness ? SR_ILED_HIGH : SR_ILED_LOW) | (led_state<<1);
- SPI1->DR = aux_reg | segment_map[active_segment];
-
- /* TODO: Measure frame rate for status report */
-
- /* Clear interrupt flag */
- TIM1->SR &= ~TIM_SR_CC1IF_Msk;
-
- GPIOA->BSRR = GPIO_BSRR_BR_0; // Debug
-}
-
-void TIM3_IRQHandler() {
- /* This handler takes about 2.1us */
- GPIOA->BSRR = GPIO_BSRR_BS_0; // Debug
-
- /* Reset SPI baudrate to 25MBd for fast MBI5026. Every couple of cycles, TIM1's ISR will set this to a slower value
- * for the slower AUX registers.*/
- SPI1->CR1 &= ~SPI_CR1_BR_Msk;
- /* Assert aux strobe reset by TIM1's IRQ handler */
- GPIOA->BSRR = GPIO_BSRR_BS_10;
-
- /* Queue LED driver data into SPI peripheral */
- uint32_t spi_word = read_fb->data[active_bit*FRAME_SIZE_WORDS + active_segment];
- SPI1->DR = spi_word>>16;
- spi_word &= 0xFFFF;
- /* Note that this only waits until the internal FIFO is ready, not until all data has been sent. */
- while (!(SPI1->SR & SPI_SR_TXE));
- SPI1->DR = spi_word;
-
- /* Advance bit. This will overflow, but that is OK since before the next invocation of this ISR, the other ISR will
- * reset it. */
- active_bit++;
- /* Schedule next bit cycle */
- TIM3->ARR = timer_period_lookup[active_bit];
-
- /* Clear interrupt flag */
- TIM3->SR &= ~TIM_SR_UIF_Msk;
-
- GPIOA->BSRR = GPIO_BSRR_BR_0; // Debug
-}
-
-void cfg_spi1() {
- /* Configure SPI controller */
- SPI1->I2SCFGR = 0;
- SPI1->CR2 &= ~SPI_CR2_DS_Msk;
- SPI1->CR2 &= ~SPI_CR2_DS_Msk;
- SPI1->CR2 |= LL_SPI_DATAWIDTH_16BIT;
-
- /* Baud rate PCLK/4 -> 12.5MHz */
- SPI1->CR1 =
- SPI_CR1_BIDIMODE
- | SPI_CR1_BIDIOE
- | SPI_CR1_SSM
- | SPI_CR1_SSI
- | SPI_CR1_SPE
- | (1<<SPI_CR1_BR_Pos)
- | SPI_CR1_MSTR
- | SPI_CR1_CPOL
- | SPI_CR1_CPHA;
- /* FIXME maybe try w/o BIDI */
-}
-
-void uart_config(void) {
- USART1->CR1 = /* 8-bit -> M1, M0 clear */
- /* RTOIE clear */
- (8 << USART_CR1_DEAT_Pos) /* 8 sample cycles/1 bit DE assertion time */
- | (8 << USART_CR1_DEDT_Pos) /* 8 sample cycles/1 bit DE assertion time */
- /* OVER8 clear. Use default 16x oversampling */
- /* CMIF clear */
- | USART_CR1_MME
- /* WAKE clear */
- /* PCE, PS clear */
- | USART_CR1_RXNEIE /* Enable receive interrupt */
- /* other interrupts clear */
- | USART_CR1_TE
- | USART_CR1_RE;
- //USART1->CR2 = USART_CR2_RTOEN; /* Timeout enable */
- USART1->CR3 = USART_CR3_DEM; /* RS485 DE enable (output on RTS) */
- /* Set divider for 25MHz baud rate @50MHz system clock. */
- int usartdiv = 25;
- USART1->BRR = usartdiv;
-
- /* And... go! */
- USART1->CR1 |= USART_CR1_UE;
-
- /* Enable receive interrupt */
- NVIC_EnableIRQ(USART1_IRQn);
- NVIC_SetPriority(USART1_IRQn, 1);
-}
-
-void trigger_error_led() {
- error_led_timeout = LED_STRETCHING_MS;
-}
-
-void trigger_comm_led() {
- comm_led_timeout = LED_STRETCHING_MS;
-}
-
-void trigger_id_led() {
- id_led_timeout = LED_STRETCHING_MS;
-}
-
-void tx_char(uint8_t c) {
- while (!(USART1->ISR & USART_ISR_TC));
- USART1->TDR = c;
-}
-
-void send_frame_formatted(uint8_t *buf, int len) {
- uint8_t *p=buf, *q=buf, *end=buf+len;
- do {
- while (*q && q!=end)
- q++;
- tx_char(q-p+1);
- while (*p && p!=end)
- tx_char(*p++);
- p++, q++;
- } while (p < end);
- tx_char('\0');
-}
-
-union {
- struct __attribute__((packed)) {
- uint8_t firmware_version,
- hardware_version,
- digit_rows,
- digit_cols;
- uint32_t uptime_s,
- framerate_millifps,
- uart_overruns,
- frame_overruns,
- invalid_frames;
- int16_t vcc_mv,
- temp_celsius;
- uint8_t nbits;
- } desc_reply;
- uint8_t byte_data[0];
-} tx_buf;
-
-void send_status_reply(void) {
- tx_buf.desc_reply.firmware_version = FIRMWARE_VERSION;
- tx_buf.desc_reply.hardware_version = HARDWARE_VERSION;
- tx_buf.desc_reply.digit_rows = NROWS;
- tx_buf.desc_reply.digit_cols = NCOLS;
- tx_buf.desc_reply.uptime_s = sys_time_seconds;
- tx_buf.desc_reply.vcc_mv = adc_vcc_mv;
- tx_buf.desc_reply.temp_celsius = adc_temp_celsius;
- tx_buf.desc_reply.nbits = nbits;
- tx_buf.desc_reply.framerate_millifps = frame_duration_us > 0 ? 1000000000 / frame_duration_us : 0;
- tx_buf.desc_reply.uart_overruns = uart_overruns;
- tx_buf.desc_reply.frame_overruns = frame_overruns;
- tx_buf.desc_reply.invalid_frames = invalid_frames;
- send_frame_formatted(tx_buf.byte_data, sizeof(tx_buf.desc_reply));
-}
-
-/* This is the higher-level protocol handler for the serial protocol. It gets passed the number of data bytes in this
- * frame (which may be zero) and returns a pointer to the buffer where the next frame should be stored.
- */
-volatile uint8_t *packet_received(int len) {
- static enum {
- PROT_ADDRESSED = 0,
- PROT_EXPECT_FRAME_SECOND_HALF = 1,
- PROT_IGNORE = 2,
- } protocol_state = PROT_IGNORE;
- /* Use mac frames as delimiters to synchronize this protocol layer */
- trigger_comm_led();
- if (len == 0) { /* Discovery packet */
- if (sys_time < 100 && sys_time_seconds == 0) { /* Only respond during the first 100ms after boot */
- send_frame_formatted((uint8_t*)&device_mac, sizeof(device_mac));
- }
-
- } else if (len == 1) { /* Command packet */
- if (protocol_state == PROT_ADDRESSED) {
- switch (rx_buf.byte_data[0]) {
- case 0x01:
- GPIOA->BSRR = GPIO_BSRR_BS_4; // Debug
- //for (int i=0; i<100; i++)
- // tick();
- send_status_reply();
- GPIOA->BSRR = GPIO_BSRR_BR_4; // Debug
- break;
- }
- } else {
- invalid_frames++;
- trigger_error_led();
- }
- protocol_state = PROT_IGNORE;
-
- } else if (len == 4) { /* Address packet */
- if (rx_buf.mac_data == device_mac) { /* we are addressed */
- protocol_state = PROT_ADDRESSED; /* start listening for frame buffer data */
- } else { /* we are not addressed */
- protocol_state = PROT_IGNORE; /* ignore packet */
- }
-
- } else if (len == sizeof(rx_buf.set_fb_rq)/2) {
- if (protocol_state == PROT_ADDRESSED) { /* First of two half-framebuffer data frames */
- protocol_state = PROT_EXPECT_FRAME_SECOND_HALF;
- /* Return second half of receive buffer */
- return rx_buf.byte_data + (sizeof(rx_buf.set_fb_rq)/2);
-
- } else if (protocol_state == PROT_EXPECT_FRAME_SECOND_HALF) { /* Second of two half-framebuffer data frames */
- /* Kick off buffer transfer. This triggers the main loop to copy data out of the receive buffer and paste it
- * properly formatted into the frame buffer. */
- if (fb_op == FB_WRITE) {
- fb_op = FB_FORMAT;
- trigger_id_led();
- } else {
- /* FIXME An overrun happend. What should we do? */
- frame_overruns++;
- trigger_error_led();
- }
-
- /* Go to "hang mode" until next zero-length packet. */
- protocol_state = PROT_IGNORE;
- }
-
- } else {
- /* FIXME An invalid packet has been received. What should we do? */
- invalid_frames++;
- trigger_error_led();
- protocol_state = PROT_IGNORE; /* go into "hang mode" until next zero-length packet */
- }
-
- /* By default, return rx_buf.byte_data . This means if an invalid protocol state is reached ("hang mode"), the next
- * frame is still written to rx_buf. This is not a problem since whatever garbage is written at that point will be
- * overwritten before the next buffer transfer. */
- return rx_buf.byte_data;
-}
-
-void USART1_IRQHandler(void) {
- /* Since a large amount of data will be shoved down this UART interface we need a more reliable and more efficient
- * way of framing than just waiting between transmissions.
- *
- * This code uses "Consistent Overhead Byte Stuffing" (COBS). For details, see its Wikipedia page[0] or the proper
- * scientific paper[1] published on it. Roughly, it works like this:
- *
- * * A frame is at most 254 bytes in length.
- * * The null byte 0x00 acts as a frame delimiter. There is no null bytes inside frames.
- * * Every frame starts with an "overhead" byte indicating the number of non-null payload bytes until the next null
- * byte in the payload, **plus one**. This means this byte can never be zero.
- * * Every null byte in the payload is replaced by *its* distance to *its* next null byte as above.
- *
- * This means, at any point the receiver can efficiently be synchronized on the next frame boundary by simply
- * waiting for a null byte. After that, only a simple state machine is necessary to strip the overhead byte and a
- * counter to then count skip intervals.
- *
- * Here is Wikipedia's table of example values:
- *
- * Unencoded data Encoded with COBS
- * 00 01 01 00
- * 00 00 01 01 01 00
- * 11 22 00 33 03 11 22 02 33 00
- * 11 22 33 44 05 11 22 33 44 00
- * 11 00 00 00 02 11 01 01 01 00
- * 01 02 ...FE FF 01 02 ...FE 00
- *
- * [0] https://en.wikipedia.org/wiki/Consistent_Overhead_Byte_Stuffing
- * [1] Cheshire, Stuart; Baker, Mary (1999). "Consistent Overhead Byte Stuffing"
- * IEEE/ACM Transactions on Networking. doi:10.1109/90.769765
- * http://www.stuartcheshire.org/papers/COBSforToN.pdf
- */
-
- /* This pointer stores where we write data. The higher-level protocol logic decides on a frame-by-frame-basis where
- * the next frame's data will be stored. */
- static volatile uint8_t *writep = rx_buf.byte_data;
- /* Index inside the current frame payload */
- static int rxpos = 0;
- /* COBS state machine. This implementation might be a little too complicated, but it works well enough and I find it
- * reasonably easy to understand. */
- static enum {
- COBS_WAIT_SYNC = 0, /* Synchronize with frame */
- COBS_WAIT_START = 1, /* Await overhead byte */
- COBS_RUNNING = 2 /* Process payload */
- } cobs_state = 0;
- /* COBS skip counter. During payload processing this contains the remaining non-null payload bytes */
- static int cobs_count = 0;
-
- if (USART1->ISR & USART_ISR_ORE) { /* Overrun handling */
- uart_overruns++;
- trigger_error_led();
- /* Reset and re-synchronize. Retry next frame. */
- rxpos = 0;
- cobs_state = COBS_WAIT_SYNC;
- /* Clear interrupt flag */
- USART1->ICR = USART_ICR_ORECF;
-
- } else { /* Data received */
- uint8_t data = USART1->RDR; /* This automatically acknowledges the IRQ */
-
- if (data == 0x00) { /* End-of-packet */
- /* Process higher protocol layers on this packet. */
- writep = packet_received(rxpos);
-
- /* Reset for next packet. */
- cobs_state = COBS_WAIT_START;
- rxpos = 0;
-
- } else { /* non-null byte */
- if (cobs_state == COBS_WAIT_SYNC) { /* Wait for null byte */
- /* ignore data */
-
- } else if (cobs_state == COBS_WAIT_START) { /* Overhead byte */
- cobs_count = data;
- cobs_state = COBS_RUNNING;
-
- } else { /* Payload byte */
- if (--cobs_count == 0) { /* Skip byte */
- cobs_count = data;
- data = 0;
- }
-
- /* Write processed payload byte to current receive buffer */
- writep[rxpos++] = data;
- }
- }
- }
-}
-
-#define ADC_OVERSAMPLING 8
-uint32_t vsense;
-void DMA1_Channel1_IRQHandler(void) {
- /* This interrupt takes either 1.2us or 13us. It can be pre-empted by the more timing-critical UART and LED timer
- * interrupts. */
- static int count = 0; /* oversampling accumulator sample count */
- static uint32_t adc_aggregate[2] = {0, 0}; /* oversampling accumulator */
-
- /* Clear the interrupt flag */
- DMA1->IFCR |= DMA_IFCR_CGIF1;
-
- adc_aggregate[0] += adc_buf[0];
- adc_aggregate[1] += adc_buf[1];
-
- if (++count == (1<<ADC_OVERSAMPLING)) {
- /* This has been copied from the code examples to section 12.9 ADC>"Temperature sensor and internal reference
- * voltage" in the reference manual with the extension that we actually measure the supply voltage instead of
- * hardcoding it. This is not strictly necessary since we're running off a bored little LDO but it's free and
- * the current supply voltage is a nice health value.
- */
- adc_vcc_mv = (3300 * VREFINT_CAL)/(adc_aggregate[0]>>ADC_OVERSAMPLING);
- int32_t temperature = (((uint32_t)TS_CAL1) - ((adc_aggregate[1]>>ADC_OVERSAMPLING) * adc_vcc_mv / 3300)) * 1000;
- temperature = (temperature/5336) + 30;
- adc_temp_celsius = temperature;
-
- count = 0;
- adc_aggregate[0] = 0;
- adc_aggregate[1] = 0;
- }
-}
-
-void adc_config(void) {
- /* The ADC is used for temperature measurement. To compute the temperature from an ADC reading of the internal
- * temperature sensor, the supply voltage must also be measured. Thus we are using two channels.
- *
- * The ADC is triggered by compare channel 4 of timer 1. The trigger is set to falling edge to trigger on compare
- * match, not overflow.
- */
- ADC1->CFGR1 = ADC_CFGR1_DMAEN | ADC_CFGR1_DMACFG | (2<<ADC_CFGR1_EXTEN_Pos) | (1<<ADC_CFGR1_EXTSEL_Pos);
- /* Clock from PCLK/4 instead of the internal exclusive high-speed RC oscillator. */
- ADC1->CFGR2 = (2<<ADC_CFGR2_CKMODE_Pos);
- /* Use the slowest available sample rate */
- ADC1->SMPR = (7<<ADC_SMPR_SMP_Pos);
- /* Internal VCC and temperature sensor channels */
- ADC1->CHSELR = ADC_CHSELR_CHSEL16 | ADC_CHSELR_CHSEL17;
- /* Enable internal voltage reference and temperature sensor */
- ADC->CCR = ADC_CCR_TSEN | ADC_CCR_VREFEN;
- /* Perform ADC calibration */
- ADC1->CR |= ADC_CR_ADCAL;
- while (ADC1->CR & ADC_CR_ADCAL)
- ;
- /* Enable ADC */
- ADC1->CR |= ADC_CR_ADEN;
- ADC1->CR |= ADC_CR_ADSTART;
-
- /* Configure DMA 1 Channel 1 to get rid of all the data */
- DMA1_Channel1->CPAR = (unsigned int)&ADC1->DR;
- DMA1_Channel1->CMAR = (unsigned int)&adc_buf;
- DMA1_Channel1->CNDTR = sizeof(adc_buf)/sizeof(adc_buf[0]);
- DMA1_Channel1->CCR = (0<<DMA_CCR_PL_Pos);
- DMA1_Channel1->CCR |=
- DMA_CCR_CIRC /* circular mode so we can leave it running indefinitely */
- | (1<<DMA_CCR_MSIZE_Pos) /* 16 bit */
- | (1<<DMA_CCR_PSIZE_Pos) /* 16 bit */
- | DMA_CCR_MINC
- | DMA_CCR_TCIE; /* Enable transfer complete interrupt. */
- DMA1_Channel1->CCR |= DMA_CCR_EN; /* Enable channel */
-
- /* triggered on transfer completion. We use this to process the ADC data */
- NVIC_EnableIRQ(DMA1_Channel1_IRQn);
- NVIC_SetPriority(DMA1_Channel1_IRQn, 3);
-}
-
int main(void) {
RCC->CR |= RCC_CR_HSEON;
while (!(RCC->CR&RCC_CR_HSERDY));
@@ -676,50 +82,13 @@ int main(void) {
| (1<<GPIO_PUPDR_PUPDR2_Pos) /* TX */
| (1<<GPIO_PUPDR_PUPDR3_Pos); /* RX */
- cfg_spi1();
-
- /* Pre-compute aux register values for timer ISR */
- for (int i=0; i<NSEGMENTS; i++) {
- segment_map[i] = 0xff00 ^ (0x100<<segment_map[i]);
- }
-
- /* Clear frame buffer */
- read_fb->brightness = 1;
- for (int i=0; i<sizeof(read_fb->data)/sizeof(uint32_t); i++) {
- read_fb->data[i] = 0xffffffff; /* FIXME this is a debug value. Should be 0x00000000; */
- }
-
- cfg_timers_led();
+ display_init();
SysTick_Config(SystemCoreClock/1000); /* 1ms interval */
- uart_config();
- adc_config();
+ serial_init();
+ adc_init();
- int last_time = 0;
while (42) {
- /* Crude LED logic. The comm, id and error LEDs each have a timeout counter that is reset to the
- * LED_STRETCHING_MS constant on an event (either a frame received correctly or some uart, framing or protocol
- * error). These timeout counters count down in milliseconds and the LEDs are set while they are non-zero. This
- * means a train of several very brief events will make the LED lit permanently.
- */
- int time_now = sys_time; /* Latch sys_time here to avoid race conditions */
- if (last_time != time_now) {
- int diff = (time_now - last_time);
-
- error_led_timeout -= diff;
- if (error_led_timeout < 0)
- error_led_timeout = 0;
-
- comm_led_timeout -= diff;
- if (comm_led_timeout < 0)
- comm_led_timeout = 0;
-
- id_led_timeout -= diff;
- if (id_led_timeout < 0)
- id_led_timeout = 0;
-
- led_state = (led_state & ~7) | (!!id_led_timeout)<<2 | (!!error_led_timeout)<<1 | (!!comm_led_timeout)<<0;
- last_time = time_now;
- }
+ led_task();
/* Process pending buffer transfer */
if (fb_op == FB_FORMAT) {