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-rw-r--r--controller/fw/Makefile15
-rw-r--r--controller/fw/src/adc.c20
-rw-r--r--controller/fw/src/con_usart.c33
-rw-r--r--controller/fw/src/con_usart.h16
-rw-r--r--controller/fw/src/dma_util.c46
-rw-r--r--controller/fw/src/dma_util.h10
-rw-r--r--controller/fw/src/freq_meas.c8
-rw-r--r--controller/fw/src/main.c80
-rw-r--r--controller/fw/src/protocol.c10
-rw-r--r--controller/fw/src/serial.c153
-rw-r--r--controller/fw/src/serial.h82
-rw-r--r--controller/fw/src/sr_global.h13
m---------controller/fw/tinyprintf0
13 files changed, 444 insertions, 42 deletions
diff --git a/controller/fw/Makefile b/controller/fw/Makefile
index 0fea8ae..50d162d 100644
--- a/controller/fw/Makefile
+++ b/controller/fw/Makefile
@@ -42,8 +42,18 @@ PRESIG_KEYFILE ?= presig_test_key.secret
# Sources
########################################################################################################################
-C_SOURCES := src/main.c src/mspdebug_wrapper.c src/spi_flash.c src/freq_meas.c src/dsss_demod.c src/adc.c \
- src/protocol.c
+C_SOURCES := src/main.c
+C_SOURCES += src/mspdebug_wrapper.c
+C_SOURCES += src/spi_flash.c
+C_SOURCES += src/freq_meas.c
+C_SOURCES += src/dsss_demod.c
+C_SOURCES += src/adc.c
+C_SOURCES += src/protocol.c
+C_SOURCES += src/serial.c
+C_SOURCES += src/con_usart.c
+C_SOURCES += src/dma_util.c
+C_SOURCES += tinyprintf/tinyprintf.c
+
C_SOURCES += $(MSPDEBUG_DIR)/drivers/jtaglib.c
CMSIS_SOURCES += $(CMSIS_DIR)/CMSIS/DSP/Source/TransformFunctions/arm_rfft_fast_init_f32.c
@@ -121,6 +131,7 @@ SYSTEM_FLAGS ?= -nostdlib -ffreestanding -nostartfiles
COMMON_CFLAGS += -Imspdebug/util -Imspdebug/drivers -Ilevmarq
COMMON_CFLAGS += -I$(CMSIS_DIR_ABS)/CMSIS/DSP/Include -I$(CMSIS_DIR_ABS)/CMSIS/Core/Include
CFLAGS += -I$(abspath musl_include_shims)
+CFLAGS += -Itinyprintf
COMMON_CFLAGS += -I$(BUILDDIR) -Isrc -Itinyaes
CFLAGS += -I$(CUBE_DIR)/Drivers/CMSIS/Device/ST/STM32F4xx/Include
diff --git a/controller/fw/src/adc.c b/controller/fw/src/adc.c
index 74f0aa9..81f5ac1 100644
--- a/controller/fw/src/adc.c
+++ b/controller/fw/src/adc.c
@@ -1,8 +1,7 @@
+#include <assert.h>
#include <string.h>
-
-#include <stm32f407xx.h>
-#include <stm32f4_isr.h>
+#include <stdint.h>
#include "adc.h"
#include "sr_global.h"
@@ -58,9 +57,10 @@ void adc_init() {
TIM1->CR2 = (2<<TIM_CR2_MMS_Pos); /* Enable update event on TRGO to provide a 1ms reference to rest of system */
TIM1->CCMR1 = (6<<TIM_CCMR1_OC1M_Pos) | (0<<TIM_CCMR1_CC1S_Pos);
TIM1->CCER = TIM_CCER_CC1E;
- TIM1->PSC = 84-1; /* 1us ticks @ f_APB2=84MHz */
- TIM1->ARR = 1000-1; /* 1ms period */
- TIM1->CCR1 = 500-1;
+ assert(apb2_timer_speed%1000000 == 0);
+ TIM1->PSC = 1000-1;
+ TIM1->ARR = (apb2_timer_speed/1000000)-1; /* 1ms period */
+ TIM1->CCR1 = 1;
TIM1->BDTR = TIM_BDTR_MOE;
/* DEBUG */
@@ -85,14 +85,12 @@ void TIM1_CC_IRQHandler(void) {
void DMA2_Stream0_IRQHandler(void) {
uint8_t isr = (DMA2->LISR >> DMA_LISR_FEIF0_Pos) & 0x3f;
-
- GPIOA->ODR ^= 1<<7;
- GPIOA->BSRR = 1<<10;
+ GPIOA->BSRR = 1<<11;
if (isr & DMA_LISR_TCIF0) { /* Transfer complete */
/* Check we're done processing the old buffer */
if (adc_fft_buf_ready_idx != -1) { /* FIXME DEBUG */
- GPIOA->BSRR = 1<<10<<16;
+ GPIOA->BSRR = 1<<11<<16;
/* clear all flags */
adc_dma->LIFCR = isr<<DMA_LISR_FEIF0_Pos;
return;
@@ -110,7 +108,7 @@ void DMA2_Stream0_IRQHandler(void) {
if (isr & DMA_LISR_TEIF0) /* Transfer error */
panic();
- GPIOA->BSRR = 1<<10<<16;
+ GPIOA->BSRR = 1<<11<<16;
/* clear all flags */
adc_dma->LIFCR = isr<<DMA_LISR_FEIF0_Pos;
}
diff --git a/controller/fw/src/con_usart.c b/controller/fw/src/con_usart.c
new file mode 100644
index 0000000..f80fa79
--- /dev/null
+++ b/controller/fw/src/con_usart.c
@@ -0,0 +1,33 @@
+
+#include <stm32f4_isr.h>
+#include "con_usart.h"
+
+volatile struct usart_desc con_usart = {
+ .le_usart = USART1,
+ .le_usart_irqn = USART1_IRQn,
+ .tx_dmas = DMA2_Stream7,
+ .tx_dma_sn = 7,
+ .tx_dma_ch = 4,
+ .tx_dma = DMA2,
+ .tx_dma_irqn = DMA2_Stream7_IRQn,
+};
+
+void con_usart_init() {
+ RCC->AHB1ENR |= RCC_AHB1ENR_GPIOAEN | RCC_AHB1ENR_DMA2EN;
+ RCC->APB2ENR |= RCC_APB2ENR_USART1EN;
+
+ /* GPIO config: A9 (TX), A10 (RX) */
+ GPIOA->MODER &= ~GPIO_MODER_MODER9_Msk & ~GPIO_MODER_MODER10_Msk;
+ GPIOA->MODER |= (2<<GPIO_MODER_MODER9_Pos) | (2<<GPIO_MODER_MODER10_Pos);
+ GPIOA->OSPEEDR &= ~GPIO_OSPEEDR_OSPEED9_Msk & ~GPIO_OSPEEDR_OSPEED10_Msk;
+ GPIOA->OSPEEDR |= (2<<GPIO_OSPEEDR_OSPEED9_Pos) | (2<<GPIO_OSPEEDR_OSPEED10_Pos);
+ GPIOA->AFR[1] &= ~GPIO_AFRH_AFSEL9_Msk & ~GPIO_AFRH_AFSEL10_Msk;
+ GPIOA->AFR[1] |= (7<<GPIO_AFRH_AFSEL9_Pos) | (7<<GPIO_AFRH_AFSEL10_Pos);
+
+ usart_dma_init(&con_usart, CON_USART_BAUDRATE);
+}
+
+void DMA2_Stream7_IRQHandler(void) {
+ usart_dma_stream_irq(&con_usart);
+}
+
diff --git a/controller/fw/src/con_usart.h b/controller/fw/src/con_usart.h
new file mode 100644
index 0000000..a1ad963
--- /dev/null
+++ b/controller/fw/src/con_usart.h
@@ -0,0 +1,16 @@
+#ifndef __CON_USART_H__
+#define __CON_USART_H__
+
+#include "serial.h"
+
+extern volatile struct usart_desc con_usart;
+
+#define con_printf(...) usart_printf(&con_usart, __VA_ARGS__)
+
+#ifndef CON_USART_BAUDRATE
+#define CON_USART_BAUDRATE 115200
+#endif
+
+void con_usart_init(void);
+
+#endif /* __CON_USART_H__ */
diff --git a/controller/fw/src/dma_util.c b/controller/fw/src/dma_util.c
new file mode 100644
index 0000000..48de215
--- /dev/null
+++ b/controller/fw/src/dma_util.c
@@ -0,0 +1,46 @@
+
+#include <assert.h>
+
+#include "dma_util.h"
+
+uint8_t dma_get_isr_and_clear(DMA_TypeDef *dma, int ch) {
+ uint8_t isr_val;
+ switch(ch) {
+ case 0:
+ isr_val = dma->LISR & 0x3f;
+ dma->LIFCR = isr_val;
+ return isr_val;
+ case 1:
+ isr_val = dma->LISR>>6 & 0x3f;
+ dma->LIFCR = isr_val<<6;
+ return isr_val;
+ case 2:
+ isr_val = dma->LISR>>16 & 0x3f;
+ dma->LIFCR = isr_val<<16;
+ return isr_val;
+ case 3:
+ isr_val = dma->LISR>>6>>16 & 0x3f;
+ dma->LIFCR = isr_val<<6<<16;
+ return isr_val;
+ case 4:
+ isr_val = dma->HISR & 0x3f;
+ dma->HIFCR = isr_val;
+ return isr_val;
+ case 5:
+ isr_val = dma->HISR>>6 & 0x3f;
+ dma->HIFCR = isr_val<<6;
+ return isr_val;
+ case 6:
+ isr_val = dma->HISR>>16 & 0x3f;
+ dma->HIFCR = isr_val<<16;
+ return isr_val;
+ case 7:
+ isr_val = dma->HISR>>6>>16 & 0x3f;
+ dma->HIFCR = isr_val<<6<<16;
+ return isr_val;
+ default:
+ assert(0);
+ return 0;
+ }
+}
+
diff --git a/controller/fw/src/dma_util.h b/controller/fw/src/dma_util.h
new file mode 100644
index 0000000..5ea2676
--- /dev/null
+++ b/controller/fw/src/dma_util.h
@@ -0,0 +1,10 @@
+#ifndef __DMA_UTIL_H__
+#define __DMA_UTIL_H__
+
+#include <stdint.h>
+
+#include "sr_global.h"
+
+uint8_t dma_get_isr_and_clear(DMA_TypeDef *dma, int ch);
+
+#endif /* __DMA_UTIL_H__ */
diff --git a/controller/fw/src/freq_meas.c b/controller/fw/src/freq_meas.c
index 020e12d..6b9b54e 100644
--- a/controller/fw/src/freq_meas.c
+++ b/controller/fw/src/freq_meas.c
@@ -136,7 +136,13 @@ int adc_buf_measure_freq(uint16_t adc_buf[FMEAS_FFT_LEN], float *out) {
DEBUG_PRINT("done.");
*/
- *out = (par[1] + first_bin) * binsize_hz;
+ float res = (par[1] + first_bin) * binsize_hz;
+ if (res < 5 || res > 150) {
+ *out = NAN;
+ return -1;
+ }
+
+ *out = res;
return 0;
}
diff --git a/controller/fw/src/main.c b/controller/fw/src/main.c
index fa5d50b..b100b16 100644
--- a/controller/fw/src/main.c
+++ b/controller/fw/src/main.c
@@ -6,15 +6,25 @@
#include <math.h>
#include <stm32f407xx.h>
+#include <stm32f4_isr.h>
#include "sr_global.h"
#include "adc.h"
#include "spi_flash.h"
#include "freq_meas.h"
#include "dsss_demod.h"
+#include "con_usart.h"
static struct spi_flash_if spif;
+unsigned int sysclk_speed = 0;
+unsigned int apb1_speed = 0;
+unsigned int apb2_speed = 0;
+unsigned int auxclk_speed = 0;
+unsigned int apb1_timer_speed = 0;
+unsigned int apb2_timer_speed = 0;
+
+struct leds leds;
void __libc_init_array(void) { /* we don't need this. */ }
void __assert_func (unused_a const char *file, unused_a int line, unused_a const char *function, unused_a const char *expr) {
@@ -24,14 +34,14 @@ void __assert_func (unused_a const char *file, unused_a int line, unused_a const
static void clock_setup(void)
{
- /* 8MHz HSE clock as PLL source.
- *
- * Divide by 8 -> 1 MHz */
+ /* 8MHz HSE clock as PLL source. */
+#define HSE_SPEED 8000000
+ /* Divide by 8 -> 1 MHz */
#define PLL_M 8
/* Multiply by 336 -> 336 MHz VCO frequency */
#define PLL_N 336
/* Divide by 4 -> 84 MHz (max freq for our chip) */
-#define PLL_P 4
+#define PLL_P 2
/* Aux clock for USB OTG, SDIO, RNG: divide VCO frequency (336 MHz) by 7 -> 48 MHz (required by USB OTG) */
#define PLL_Q 7
@@ -54,10 +64,10 @@ static void clock_setup(void)
/* set AHB prescaler to /1 (CFGR:bits 7:4) */
RCC->CFGR |= (0 << RCC_CFGR_HPRE_Pos);
- /* set ABP1 prescaler to 2 -> 42MHz */
- RCC->CFGR |= (4 << RCC_CFGR_PPRE1_Pos);
- /* set ABP2 prescaler to 1 -> 84MHz */
- RCC->CFGR |= (0 << RCC_CFGR_PPRE2_Pos);
+ /* set ABP1 prescaler to 4 -> 42MHz */
+ RCC->CFGR |= (5 << RCC_CFGR_PPRE1_Pos);
+ /* set ABP2 prescaler to 2 -> 84MHz */
+ RCC->CFGR |= (4 << RCC_CFGR_PPRE2_Pos);
if (RCC->CR & RCC_CR_PLLON)
asm volatile ("bkpt");
@@ -79,6 +89,13 @@ static void clock_setup(void)
| RCC_PLLCFGR_PLLSRC; /* select HSE as PLL source */
RCC->CR |= RCC_CR_PLLON;
+ sysclk_speed = HSE_SPEED / PLL_M * PLL_N / PLL_P;
+ auxclk_speed = HSE_SPEED / PLL_M * PLL_N / PLL_Q;
+ apb1_speed = sysclk_speed / 4;
+ apb1_timer_speed = apb1_speed * 2;
+ apb2_speed = sysclk_speed / 2;
+ apb2_timer_speed = apb2_speed * 2;
+
/* Wait for main PLL */
while(!(RCC->CR & RCC_CR_PLLRDY))
;
@@ -170,7 +187,7 @@ int main(void)
GPIOC->MODER &= ~GPIO_MODER_MODER9_Msk;
GPIOC->MODER |= (2<<GPIO_MODER_MODER9_Pos);
GPIOC->AFR[1] &= ~GPIO_AFRH_AFSEL9_Msk;
- GPIOC->OSPEEDR |= (3<<GPIO_OSPEEDR_OSPEED9_Pos); /* SCK */
+ GPIOC->OSPEEDR |= (3<<GPIO_OSPEEDR_OSPEED9_Pos);
RCC->CFGR |= (6<<RCC_CFGR_MCO2PRE_Pos) | (3<<RCC_CFGR_MCO2_Pos);
#endif
@@ -179,6 +196,9 @@ int main(void)
}
clock_setup();
+ con_usart_init();
+ con_printf("\033[2J\033[HBooting...\r\n");
+
led_setup();
spi_flash_setup();
adc_init();
@@ -190,30 +210,38 @@ int main(void)
GPIOA->AFR[1] &= ~GPIO_AFRH_AFSEL8_Msk;
GPIOA->AFR[1] |= 1<<GPIO_AFRH_AFSEL8_Pos;
- GPIOA->MODER |= (1<<GPIO_MODER_MODER9_Pos) | (1<<GPIO_MODER_MODER10_Pos) | (1<<GPIO_MODER_MODER11_Pos) |
- (1<<GPIO_MODER_MODER12_Pos) | (1<<GPIO_MODER_MODER15_Pos);
+ GPIOA->MODER |= (1<<GPIO_MODER_MODER11_Pos) | (1<<GPIO_MODER_MODER12_Pos) | (1<<GPIO_MODER_MODER15_Pos);
#endif
+ con_printf("Booted.\r\n");
while (23) {
if (adc_fft_buf_ready_idx != -1) {
- GPIOA->BSRR = 1<<9;
+ GPIOA->BSRR = 1<<11;
adc_fft_buf_ready_idx = !adc_fft_buf_ready_idx; /* DEBUG */
memcpy(adc_fft_buf[!adc_fft_buf_ready_idx], adc_fft_buf[adc_fft_buf_ready_idx] + FMEAS_FFT_LEN/2, sizeof(adc_fft_buf[0][0]) * FMEAS_FFT_LEN/2);
- GPIOA->BSRR = 1<<9<<16;
- GPIOA->BSRR = 1<<11;
+ GPIOA->BSRR = 1<<11<<16;
+ GPIOA->BSRR = 1<<11;
float out;
if (adc_buf_measure_freq(adc_fft_buf[adc_fft_buf_ready_idx], &out)) {
+ con_printf("%012d: measurement error\r\n", freq_sample_ts);
measurement_errors++;
+ GPIOA->BSRR = 1<<7;
debug_last_freq = NAN;
} else {
debug_last_freq = out;
-
- /*
+ con_printf("%012d: %2d.%03d Hz\r\n", freq_sample_ts, (int)out, (int)(out * 1000) % 1000);
+ /* frequency ok led */
+ if (48 < out && out < 52)
+ GPIOA->BSRR = 1<<7<<16;
+ else
+ GPIOA->BSRR = 1<<7;
+
+ GPIOA->BSRR = 1<<12;
dsss_demod_init(&demod_state);
dsss_demod_step(&demod_state, out, freq_sample_ts);
- */
+ GPIOA->BSRR = 1<<12<<16;
}
GPIOA->BSRR = 1<<11<<16;
@@ -226,38 +254,38 @@ int main(void)
}
void NMI_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #1");
}
void HardFault_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #2");
}
void MemManage_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #3");
}
void BusFault_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #4");
}
void UsageFault_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #5");
}
void SVC_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #6");
}
void DebugMon_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #7");
}
void PendSV_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #8");
}
void SysTick_Handler(void) {
- asm volatile ("bkpt");
+ asm volatile ("bkpt #9");
}
diff --git a/controller/fw/src/protocol.c b/controller/fw/src/protocol.c
index 17020bd..bbee5ef 100644
--- a/controller/fw/src/protocol.c
+++ b/controller/fw/src/protocol.c
@@ -1,7 +1,13 @@
#include "sr_global.h"
#include "dsss_demod.h"
+#include "con_usart.h"
-void handle_dsss_received(uint8_t unused_a data[static TRANSMISSION_SYMBOLS]) {
- asm volatile ("bkpt");
+void handle_dsss_received(uint8_t data[static TRANSMISSION_SYMBOLS]) {
+ con_printf("DSSS data received: ");
+ for (int i=0; i<TRANSMISSION_SYMBOLS; i++) {
+ int x = (data[i]>>1) * (data[i]&1 ? 1 : -1);
+ con_printf("%3d ", x);
+ }
+ con_printf("\r\n");
}
diff --git a/controller/fw/src/serial.c b/controller/fw/src/serial.c
new file mode 100644
index 0000000..71e1868
--- /dev/null
+++ b/controller/fw/src/serial.c
@@ -0,0 +1,153 @@
+#include <string.h>
+#include <stdarg.h>
+#include <stdlib.h>
+
+#include "dma_util.h"
+#include "sr_global.h"
+#include "serial.h"
+
+#include <tinyprintf.h>
+
+static void usart_schedule_dma(volatile struct usart_desc *us);
+static void usart_dma_reset(volatile struct usart_desc *us);
+static void usart_putc_nonblocking_tpf(void *us, char c);
+
+void usart_dma_reset(volatile struct usart_desc *us) {
+ us->tx_buf.xfr_start = -1;
+ us->tx_buf.xfr_end = 0;
+ us->tx_buf.wr_pos = 0;
+ us->tx_buf.wr_idx = 0;
+ us->tx_buf.xfr_next = 0;
+ us->tx_buf.wraparound = false;
+
+ for (size_t i=0; i<ARRAY_LENGTH(us->tx_buf.chunk_end); i++)
+ us->tx_buf.chunk_end[i] = -1;
+}
+
+void usart_dma_init(volatile struct usart_desc *us, unsigned int baudrate) {
+ usart_dma_reset(us);
+
+ /* Configure DMA 1 Channel 2 to handle uart transmission */
+ us->tx_dmas->PAR = (uint32_t)&(us->le_usart->DR);
+ us->tx_dmas->CR =
+ (us->tx_dma_ch<<DMA_SxCR_CHSEL_Pos)
+ | (0<<DMA_SxCR_PL_Pos)
+ | (1<<DMA_SxCR_DIR_Pos)
+ | (0<<DMA_SxCR_MSIZE_Pos) /* 8 bit */
+ | (0<<DMA_SxCR_PSIZE_Pos) /* 8 bit */
+ | DMA_SxCR_MINC
+ | DMA_SxCR_TCIE; /* Enable transfer complete interrupt. */
+
+ /* triggered on transfer completion. We use this to process the ADC data */
+ NVIC_EnableIRQ(us->tx_dma_irqn);
+ NVIC_SetPriority(us->tx_dma_irqn, 30);
+
+ us->le_usart->CR1 = USART_CR1_TE;
+ /* Set divider for 115.2kBd @48MHz system clock. */
+ us->le_usart->BRR = apb2_speed * 16 / baudrate / 16; /* 250kBd */
+ us->le_usart->CR3 |= USART_CR3_DMAT; /* TX DMA enable */
+
+ /* And... go! */
+ us->le_usart->CR1 |= USART_CR1_UE;
+}
+
+void usart_schedule_dma(volatile struct usart_desc *us) {
+ volatile struct dma_tx_buf *buf = &us->tx_buf;
+
+ ssize_t xfr_start, xfr_end, xfr_len;
+ if (buf->wraparound) {
+ buf->wraparound = false;
+ xfr_start = 0;
+ xfr_len = buf->xfr_end;
+ xfr_end = buf->xfr_end;
+
+ } else {
+ if (buf->chunk_end[buf->xfr_next] == -1)
+ return; /* Nothing to trasnmit */
+
+ xfr_start = buf->xfr_end;
+ xfr_end = buf->chunk_end[buf->xfr_next];
+ buf->chunk_end[buf->xfr_next] = -1;
+ buf->xfr_next = (buf->xfr_next + 1) % ARRAY_LENGTH(buf->chunk_end);
+
+ if (xfr_end > xfr_start) { /* no wraparound */
+ xfr_len = xfr_end - xfr_start;
+
+ } else { /* wraparound */
+ if (xfr_end != 0)
+ buf->wraparound = true;
+ xfr_len = sizeof(us->data) - xfr_start;
+ }
+ }
+
+ buf->xfr_start = xfr_start;
+ buf->xfr_end = xfr_end;
+
+ us->comm_led = 100;
+
+ /* initiate transmission of new buffer */
+ us->tx_dmas->M0AR = (uint32_t)(us->data + xfr_start);
+ us->tx_dmas->NDTR = xfr_len;
+ us->tx_dmas->CR |= DMA_SxCR_EN;
+}
+
+void usart_dma_stream_irq(volatile struct usart_desc *us) {
+ uint8_t iflags = dma_get_isr_and_clear(us->tx_dma, us->tx_dma_sn);
+
+ if (iflags & DMA_LISR_TCIF0) { /* Transfer complete */
+ us->tx_dmas->CR &= ~DMA_SxCR_EN;
+ //if (us->tx_buf.wraparound)
+ usart_schedule_dma(us);
+ }
+
+ if (iflags & DMA_LISR_FEIF0)
+ us->tx_errors++;
+}
+
+int usart_putc_nonblocking(volatile struct usart_desc *us, char c) {
+ volatile struct dma_tx_buf *buf = &us->tx_buf;
+
+ if (buf->wr_pos == buf->xfr_start) {
+ us->tx_byte_overruns++;
+ return -EBUSY;
+ }
+
+ buf->data[buf->wr_pos] = c;
+ buf->wr_pos = (buf->wr_pos + 1) % sizeof(us->data);
+ return 0;
+}
+
+void usart_putc_nonblocking_tpf(void *us, char c) {
+ usart_putc_nonblocking((struct usart_desc *)us, c);
+}
+
+
+int usart_send_chunk_nonblocking(volatile struct usart_desc *us, const char *chunk, size_t chunk_len) {
+ for (size_t i=0; i<chunk_len; i++)
+ usart_putc_nonblocking(us, chunk[i]);
+
+ return usart_flush(us);
+}
+
+int usart_flush(volatile struct usart_desc *us) {
+ /* Find a free slot for this chunk */
+ if (us->tx_buf.chunk_end[us->tx_buf.wr_idx] != -1) {
+ us->tx_chunk_overruns++;
+ return -EBUSY;
+ }
+
+ us->tx_buf.chunk_end[us->tx_buf.wr_idx] = us->tx_buf.wr_pos;
+ us->tx_buf.wr_idx = (us->tx_buf.wr_idx + 1) % ARRAY_LENGTH(us->tx_buf.chunk_end);
+
+ if (!(us->tx_dmas->CR & DMA_SxCR_EN))
+ usart_schedule_dma(us);
+ return 0;
+}
+
+int usart_printf(volatile struct usart_desc *us, char *fmt, ...) {
+ va_list va;
+ va_start(va, fmt);
+ tfp_format((void *)us, usart_putc_nonblocking_tpf, fmt, va);
+ return usart_flush(us);
+}
+
diff --git a/controller/fw/src/serial.h b/controller/fw/src/serial.h
new file mode 100644
index 0000000..02f6f5d
--- /dev/null
+++ b/controller/fw/src/serial.h
@@ -0,0 +1,82 @@
+/*
+ * This file is part of the libusbhost library
+ * hosted at http://github.com/libusbhost/libusbhost
+ *
+ * Copyright (C) 2015 Amir Hammad <amir.hammad@hotmail.com>
+ *
+ *
+ * libusbhost is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef __SERIAL_H__
+#define __SERIAL_H__
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <stdbool.h>
+
+#include "sr_global.h"
+
+struct dma_tx_buf {
+ /* The following fields are accessed only from DMA ISR */
+ ssize_t xfr_start; /* Start index of running DMA transfer */
+ ssize_t xfr_end; /* End index of running DMA transfer plus one */
+ bool wraparound;
+ ssize_t xfr_next;
+
+ /* The following fields are written only from non-interrupt code */
+ ssize_t wr_pos; /* Next index to be written */
+ ssize_t wr_idx;
+ ssize_t chunk_end[8];
+
+/* Make GCC shut up about the zero-size array member. */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpedantic"
+ /* Written outside ISR by usart_send_chunk_nonblocking, read via DMA */
+ uint8_t data[0];
+#pragma GCC diagnostic pop
+};
+
+struct usart_desc {
+ struct dma_tx_buf tx_buf;
+ uint8_t data[512];
+
+ uint32_t tx_chunk_overruns, tx_byte_overruns;
+ uint32_t tx_errors;
+
+ volatile uint8_t rx_buf[32];
+
+ int comm_led;
+
+ USART_TypeDef *le_usart;
+ int le_usart_irqn;
+ DMA_Stream_TypeDef *tx_dmas;
+ int tx_dma_sn;
+ int tx_dma_ch;
+ DMA_TypeDef *tx_dma;
+ int tx_dma_irqn;
+};
+
+void usart_dma_init(volatile struct usart_desc *us, unsigned int baudrate);
+int usart_send_chunk_nonblocking(volatile struct usart_desc *us, const char *chunk, size_t chunk_len);
+int usart_putc_nonblocking(volatile struct usart_desc *us, char c);
+
+void usart_dma_stream_irq(volatile struct usart_desc *us);
+int usart_flush(volatile struct usart_desc *us);
+int usart_printf(volatile struct usart_desc *us, char *fmt, ...);
+
+#endif // __SERIAL_H__
diff --git a/controller/fw/src/sr_global.h b/controller/fw/src/sr_global.h
index ac77359..451cce0 100644
--- a/controller/fw/src/sr_global.h
+++ b/controller/fw/src/sr_global.h
@@ -2,12 +2,25 @@
#define __SR_GLOBAL_H__
#include <stdint.h>
+#include <stm32f407xx.h>
+#include <stm32f4_isr.h>
+#include <sys/types.h>
#define UNUSED(x) ((void) x)
#define ARRAY_LENGTH(x) (sizeof(x) / sizeof(x[0]))
#define unused_a __attribute__((unused))
+extern unsigned int sysclk_speed;
+extern unsigned int apb1_speed;
+extern unsigned int apb2_speed;
+extern unsigned int auxclk_speed;
+extern unsigned int apb1_timer_speed;
+extern unsigned int apb2_timer_speed;
+
+extern struct leds {
+ unsigned int comm_tx;
+} leds;
static inline uint16_t htole(uint16_t val) { return val; }
void __libc_init_array(void);
diff --git a/controller/fw/tinyprintf b/controller/fw/tinyprintf
new file mode 160000
+Subproject 2ee30120ec15e321566b43f83c731d060bb437f