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-rw-r--r--protocol/serial_soft.c119
1 files changed, 102 insertions, 17 deletions
diff --git a/protocol/serial_soft.c b/protocol/serial_soft.c
index beddc353c..e8870bcd7 100644
--- a/protocol/serial_soft.c
+++ b/protocol/serial_soft.c
@@ -43,15 +43,47 @@ POSSIBILITY OF SUCH DAMAGE.
43 43
44/* 44/*
45 * Stupid Inefficient Busy-wait Software Serial 45 * Stupid Inefficient Busy-wait Software Serial
46 * is still useful for negative logic signal like Sun protocol not supported by hardware USART. 46 * which is still useful for negative logic signal like Sun protocol
47 * if it is not supported by hardware UART.
48 *
49 * TODO: delay is not accurate enough. Instruction cycle should be counted and inline assemby is needed.
47 */ 50 */
48 51
49#define WAIT_US (1000000/SERIAL_BAUD) 52#define WAIT_US (1000000L/SERIAL_SOFT_BAUD)
53
54#ifdef SERIAL_SOFT_LOGIC_NEGATIVE
55 #define SERIAL_SOFT_RXD_IN() !(SERIAL_SOFT_RXD_READ())
56 #define SERIAL_SOFT_TXD_ON() SERIAL_SOFT_TXD_LO()
57 #define SERIAL_SOFT_TXD_OFF() SERIAL_SOFT_TXD_HI()
58#else
59 #define SERIAL_SOFT_RXD_IN() !!(SERIAL_SOFT_RXD_READ())
60 #define SERIAL_SOFT_TXD_ON() SERIAL_SOFT_TXD_HI()
61 #define SERIAL_SOFT_TXD_OFF() SERIAL_SOFT_TXD_LO()
62#endif
63
64#ifdef SERIAL_SOFT_PARITY_EVEN
65 #define SERIAL_SOFT_PARITY_VAL 0
66#elif defined(SERIAL_SOFT_PARITY_ODD)
67 #define SERIAL_SOFT_PARITY_VAL 1
68#endif
69
70/* debug for signal timing, see debug pin with oscilloscope */
71#define SERIAL_SOFT_DEBUG
72#ifdef SERIAL_SOFT_DEBUG
73 #define SERIAL_SOFT_DEBUG_INIT() (DDRD |= 1<<7)
74 #define SERIAL_SOFT_DEBUG_TGL() (PORTD ^= 1<<7)
75#else
76 #define SERIAL_SOFT_DEBUG_INIT()
77 #define SERIAL_SOFT_DEBUG_TGL()
78#endif
79
50 80
51void serial_init(void) 81void serial_init(void)
52{ 82{
53 SERIAL_RXD_INIT(); 83 SERIAL_SOFT_DEBUG_INIT();
54 SERIAL_TXD_INIT(); 84
85 SERIAL_SOFT_RXD_INIT();
86 SERIAL_SOFT_TXD_INIT();
55} 87}
56 88
57/* RX ring buffer */ 89/* RX ring buffer */
@@ -60,6 +92,7 @@ static uint8_t rbuf[RBUF_SIZE];
60static uint8_t rbuf_head = 0; 92static uint8_t rbuf_head = 0;
61static uint8_t rbuf_tail = 0; 93static uint8_t rbuf_tail = 0;
62 94
95
63uint8_t serial_recv(void) 96uint8_t serial_recv(void)
64{ 97{
65 uint8_t data = 0; 98 uint8_t data = 0;
@@ -72,68 +105,120 @@ uint8_t serial_recv(void)
72 return data; 105 return data;
73} 106}
74 107
108int16_t serial_recv2(void)
109{
110 uint8_t data = 0;
111 if (rbuf_head == rbuf_tail) {
112 return -1;
113 }
114
115 data = rbuf[rbuf_tail];
116 rbuf_tail = (rbuf_tail + 1) % RBUF_SIZE;
117 return data;
118}
119
75void serial_send(uint8_t data) 120void serial_send(uint8_t data)
76{ 121{
77 /* signal state: IDLE: ON, START: OFF, STOP: ON, DATA0: OFF, DATA1: ON */ 122 /* signal state: IDLE: ON, START: OFF, STOP: ON, DATA0: OFF, DATA1: ON */
78 /* start bit */
79 SERIAL_TXD_OFF();
80 _delay_us(WAIT_US);
81 123
82#ifdef SERIAL_BIT_ORDER_MSB 124#ifdef SERIAL_SOFT_BIT_ORDER_MSB
83 uint8_t mask = 0x80; 125 uint8_t mask = 0x80;
84#else 126#else
85 uint8_t mask = 0x01; 127 uint8_t mask = 0x01;
86#endif 128#endif
129
130 uint8_t parity = 0;
131
132 /* start bit */
133 SERIAL_SOFT_TXD_OFF();
134 _delay_us(WAIT_US);
135
87 while (mask) { 136 while (mask) {
88 if (data&mask) { SERIAL_TXD_ON(); } else { SERIAL_TXD_OFF(); } 137 if (data&mask) {
138 SERIAL_SOFT_TXD_ON();
139 parity ^= 1;
140 } else {
141 SERIAL_SOFT_TXD_OFF();
142 }
89 _delay_us(WAIT_US); 143 _delay_us(WAIT_US);
90 144
91#ifdef SERIAL_BIT_ORDER_MSB 145#ifdef SERIAL_SOFT_BIT_ORDER_MSB
92 mask >>= 1; 146 mask >>= 1;
93#else 147#else
94 mask <<= 1; 148 mask <<= 1;
95#endif 149#endif
96 } 150 }
97 151
152#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
153 /* to center of parity bit */
154 if (parity != SERIAL_SOFT_PARITY_VAL) {
155 SERIAL_SOFT_TXD_ON();
156 } else {
157 SERIAL_SOFT_TXD_OFF();
158 }
159 _delay_us(WAIT_US);
160#endif
161
98 /* stop bit */ 162 /* stop bit */
99 SERIAL_TXD_ON(); 163 SERIAL_SOFT_TXD_ON();
100 _delay_us(WAIT_US); 164 _delay_us(WAIT_US);
101} 165}
102 166
103/* detect edge of start bit */ 167/* detect edge of start bit */
104ISR(SERIAL_RXD_VECT) 168ISR(SERIAL_SOFT_RXD_VECT)
105{ 169{
106 SERIAL_RXD_INT_ENTER() 170 SERIAL_SOFT_DEBUG_TGL();
171 SERIAL_SOFT_RXD_INT_ENTER()
107 172
108 uint8_t data = 0; 173 uint8_t data = 0;
109#ifdef SERIAL_BIT_ORDER_MSB 174
175#ifdef SERIAL_SOFT_BIT_ORDER_MSB
110 uint8_t mask = 0x80; 176 uint8_t mask = 0x80;
111#else 177#else
112 uint8_t mask = 0x01; 178 uint8_t mask = 0x01;
113#endif 179#endif
180
181 uint8_t parity = 0;
182
114 /* to center of start bit */ 183 /* to center of start bit */
115 _delay_us(WAIT_US/2); 184 _delay_us(WAIT_US/2);
185 SERIAL_SOFT_DEBUG_TGL();
116 do { 186 do {
117 /* to center of next bit */ 187 /* to center of next bit */
118 _delay_us(WAIT_US); 188 _delay_us(WAIT_US);
119 189
120 if (SERIAL_RXD_READ()) { 190 SERIAL_SOFT_DEBUG_TGL();
191 if (SERIAL_SOFT_RXD_IN()) {
121 data |= mask; 192 data |= mask;
193 parity ^= 1;
122 } 194 }
123#ifdef SERIAL_BIT_ORDER_MSB 195#ifdef SERIAL_SOFT_BIT_ORDER_MSB
124 mask >>= 1; 196 mask >>= 1;
125#else 197#else
126 mask <<= 1; 198 mask <<= 1;
127#endif 199#endif
128 } while (mask); 200 } while (mask);
201
202#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
203 /* to center of parity bit */
204 _delay_us(WAIT_US);
205 if (SERIAL_SOFT_RXD_IN()) { parity ^= 1; }
206 SERIAL_SOFT_DEBUG_TGL();
207#endif
208
129 /* to center of stop bit */ 209 /* to center of stop bit */
130 _delay_us(WAIT_US); 210 _delay_us(WAIT_US);
131 211
132 uint8_t next = (rbuf_head + 1) % RBUF_SIZE; 212 uint8_t next = (rbuf_head + 1) % RBUF_SIZE;
213#if defined(SERIAL_SOFT_PARITY_EVEN) || defined(SERIAL_SOFT_PARITY_ODD)
214 if ((parity == SERIAL_SOFT_PARITY_VAL) && next != rbuf_tail) {
215#else
133 if (next != rbuf_tail) { 216 if (next != rbuf_tail) {
217#endif
134 rbuf[rbuf_head] = data; 218 rbuf[rbuf_head] = data;
135 rbuf_head = next; 219 rbuf_head = next;
136 } 220 }
137 221
138 SERIAL_RXD_INT_EXIT(); 222 SERIAL_SOFT_RXD_INT_EXIT();
223 SERIAL_SOFT_DEBUG_TGL();
139} 224}