1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
#include "arch.h"
#include "arch/stm32l4xxx/peripherals/clock.h"
#include "arch/stm32l4xxx/peripherals/dma.h"
#include "arch/stm32l4xxx/peripherals/gpio.h"
#include "arch/stm32l4xxx/peripherals/system.h"
#include "arch/stm32l4xxx/peripherals/usart.h"
#include "arch/stm32l4xxx/peripherals/nvic.h"
#include "arch/stm32l4xxx/peripherals/irq.h"
#include "kern/dma/dma_manager.h"
#include "kern/gpio/gpio_manager.h"
#include "kern/gpio/sysled.h"
#include "kern/delay.h"
#include "kern/mem.h"
#include "kern/string.h"
/** Overrides the default systick irq handler. */
void on_systick()
{
static int is_on = 0;
gpio_reserved_pin_t sysled = get_sysled();
if (is_on) {
set_gpio_pin_low(sysled);
} else {
set_gpio_pin_high(sysled);
}
is_on = ! is_on;
}
void setup_usart2(uint32_t baud_rate)
{
enable_hsi(&RCC, true);
int ec = 0;
gpio_enable_alternate_function(
GPIO_ALTERNATE_FUNCTION_USART2_TX, GPIO_PIN_PA2, &ec);
if (ec) {
unhandled_isr(ec & 0xff);
}
gpio_enable_alternate_function(
GPIO_ALTERNATE_FUNCTION_USART2_RX, GPIO_PIN_PA15, &ec);
if (ec) {
unhandled_isr(ec & 0xff);
}
set_usart2_clock_src(&RCC, USART_CLK_SRC_HSI16);
set_usart2_clock_enabled(&RCC, USART_CLK_SRC_HSI16);
/* De-assert reset of USART2 */
regset(RCC.apb1rst1_r, rcc_usart2rst, 0);
USART2.c_r1 = 0;
USART2.c_r2 = 0;
USART2.c_r3 = 0;
usart_set_divisor(&USART2, 16000000 / baud_rate);
}
#ifdef ARCH_STM32L4
/* Main function. This gets executed from the interrupt vector defined above. */
int main()
{
/* Enable a higher clock frequency. */
set_system_clock_MHz(80);
setup_usart2(115200);
regset(USART2.c_r1, usart_txeie, 1);
regset(USART2.c_r1, usart_rxneie, 1);
usart_enable_dma(&USART2, USART_ENABLE_TX);
usart_set_enabled(&USART2, USART_ENABLE_TX | USART_ENABLE_RX);
dma_opts_t opts = DEFAULT_DMA_OPTS;
opts.transfer_complete_interrupt_enable = 1;
int ec = 0;
dma_mem2p_channel_t dma_chan =
select_dma_channel_mem2p(DMA1_PERIPH_USART2_TX, &opts, &ec);
enable_interrupt(dma_channel_get_interrupt(dma_chan.c_));
if (ec) {
usart_printf(&USART2, "Select DMA channel failed :( %d\n", ec);
for (;;);
}
// const char* thing = "Good Thing This Works!";
char* str = halloc(128);
kstrcpy(str, "Hello, Heap!");
usart_printf(&USART2, "DATA_SEGMENT_START %p\n", &DATA_SEGMENT_START);
usart_printf(&USART2, "DATA_SEGMENT_STOP: %p\n", &DATA_SEGMENT_STOP);
usart_printf(&USART2, "str at: %p\n", str);
usart_printf(&USART2, "str: %s\n", str);
// usart_printf(&USART2, "%s\n", thing);
// regset(USART2.ic_r, usart_tccf, 1);
// dma_mem2p_initiate_transfer(dma_chan, thing, strlen(thing));
gpio_reserved_pin_t sysled = get_sysled();
set_gpio_pin_high(sysled);
// usart_printf(&USART2, "Start Configuring Countdown!\n");
/* Set the countdown to start from 1,000,0000. */
SCB.strv_r = 1000000;
/* Enable interrupts. */
regset(SCB.stcs_r, scb_tickint, 1);
/* Start the systick. */
regset(SCB.stcs_r, scb_enable, 1);
// usart_printf(&USART2, "Start Countdown Started!\n");
}
#endif
|
