blob: accb1591bdba8c7c7d210c1bd0899a3f02aef484 (
plain)
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
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
#include <stm32f1xx.h>
#pragma GCC diagnostic pop
#include <system_stm32f1xx.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
#include <8b10b.h>
/* Part number: STM32F030F4C6 */
static volatile unsigned int sys_time;
uint32_t get_tick() {
return SysTick->VAL;
}
static volatile struct {
int current_symbol, next_symbol;
struct state_8b10b_enc st;
} txstate;
#define NO_SYMBOL (DECODER_RETURN_CODE_LAST + 1)
int main(void) {
/* External crystal: 8MHz */
RCC->CR |= RCC_CR_HSEON;
while (!(RCC->CR&RCC_CR_HSERDY));
/* Sysclk = HCLK = 48MHz */
RCC->CFGR = (RCC->CFGR & (~RCC_CFGR_PLLMULL_Msk & ~RCC_CFGR_SW_Msk & ~RCC_CFGR_PPRE1_Msk & ~RCC_CFGR_PPRE2_Msk &
~RCC_CFGR_HPRE_Msk))
| (10<<RCC_CFGR_PLLMULL_Pos) | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | (4<<RCC_CFGR_PPRE1_Pos) |
(4<<RCC_CFGR_PPRE2_Pos);
RCC->CR |= RCC_CR_PLLON;
while (!(RCC->CR&RCC_CR_PLLRDY));
/* Switch to PLL */
RCC->CFGR |= (2<<RCC_CFGR_SW_Pos);
//RCC->CFGR = (RCC->CFGR & (~RCC_CFGR_PPRE1_Msk & ~RCC_CFGR_PPRE2_Msk))
// | (4<<RCC_CFGR_PPRE1_Pos) | (4<<RCC_CFGR_PPRE2_Pos);
SystemCoreClockUpdate();
RCC->APB2ENR |= RCC_APB2ENR_IOPAEN | RCC_APB2ENR_IOPBEN | RCC_APB2ENR_IOPCEN | RCC_APB2ENR_TIM1EN;
GPIOA->CRH =
(2<<GPIO_CRH_CNF8_Pos) | (1<<GPIO_CRH_MODE8_Pos); /* PA8 - low side */
GPIOB->CRH =
(2<<GPIO_CRH_CNF13_Pos) | (1<<GPIO_CRH_MODE13_Pos); /* PB13 - high side */
GPIOC->CRH =
(0<<GPIO_CRH_CNF13_Pos) | (1<<GPIO_CRH_MODE13_Pos); /* PC13 - LED */
/* TIM1 running off 24MHz APB2 clk, T=41.667ns */
TIM1->CR1 = 0; /* Disable ARR preload (double-buffering) */
TIM1->PSC = 24-1; /* Prescaler 24 -> f=1MHz/T=1us */
TIM1->DIER = TIM_DIER_UIE; /* Enable update (overflow) interrupt */
TIM1->CCMR1 = 6<<TIM_CCMR1_OC1M_Pos | TIM_CCMR1_OC1PE; /* Configure output compare unit 1 to PWM mode 1, enable CCR1
preload */
TIM1->CCER = TIM_CCER_CC1NE | TIM_CCER_CC1E; /* Confiugre CH1 to complementary outputs */
TIM1->BDTR = TIM_BDTR_MOE | (0xc0 | (63-32))<<TIM_BDTR_DTG_Pos; /* Enable MOE on next update event, i.e. on initial timer load.
Set dead-time to 100us. */
TIM1->CR1 |= TIM_CR1_CEN;
TIM1->ARR = 1000-1; /* Set f=1.0kHz/T=1.0ms */
xfr_8b10b_encode_reset(&txstate.st);
txstate.current_symbol = txstate.next_symbol = xfr_8b10b_encode(&txstate.st, K28_1) | 1<<10;
TIM1->EGR |= TIM_EGR_UG;
NVIC_EnableIRQ(TIM1_UP_IRQn);
NVIC_SetPriority(TIM1_UP_IRQn, 3<<4);
uint8_t txbuf[128];
int txpos = -1;
/* FIXME test code */
for (int i=0; i<sizeof(txbuf); i++)
txbuf[i] = i;
/* FIXME end test code */
while (42) {
if (txstate.next_symbol == -NO_SYMBOL) {
txstate.next_symbol = xfr_8b10b_encode(&txstate.st, K28_1);
//if (txpos == -1)
// txstate.next_symbol = xfr_8b10b_encode(&txstate.st, K28_1);
//else
// txstate.next_symbol = xfr_8b10b_encode(&txstate.st, txbuf[txpos]);
txpos++;
if (txpos == sizeof(txbuf))
txpos = -1;
}
}
}
void TIM1_UP_IRQHandler() {
// FIXME debug code
static int debug_bit = 0;
debug_bit = !debug_bit;
TIM1->SR &= ~TIM_SR_UIF;
int sym = txstate.current_symbol;
int bit = sym&1;
sym >>= 1;
if (sym == 1) { /* last bit shifted out */
sym = txstate.next_symbol | 1<<10;
txstate.next_symbol = -NO_SYMBOL;
}
txstate.current_symbol = sym;
TIM1->CCR1 = debug_bit ? 0xffff : 0x0000;
}
void NMI_Handler(void) {
}
void HardFault_Handler(void) __attribute__((naked));
void HardFault_Handler() {
asm volatile ("bkpt");
}
void SVC_Handler(void) {
}
void PendSV_Handler(void) {
}
void SysTick_Handler(void) {
sys_time++;
}
void _init(void) {
}
void MemManage_Handler(void) __attribute__((naked));
void MemManage_Handler() {
asm volatile ("bkpt");
}
void BusFault_Handler(void) __attribute__((naked));
void BusFault_Handler() {
asm volatile ("bkpt");
}
|
