-
Notifications
You must be signed in to change notification settings - Fork 0
/
serial6.c
455 lines (407 loc) · 12.7 KB
/
serial6.c
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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
/* Teensyduino Core Library
* http://www.pjrc.com/teensy/
* Copyright (c) 2017 PJRC.COM, LLC.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* 1. The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* 2. If the Software is incorporated into a build system that allows
* selection among a list of target devices, then similar target
* devices manufactured by PJRC.COM must be included in the list of
* target devices and selectable in the same manner.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "kinetis.h"
#include "core_pins.h"
#include "HardwareSerial.h"
#include <stddef.h>
#ifdef HAS_KINETISK_UART5
////////////////////////////////////////////////////////////////
// Tunable parameters (relatively safe to edit these numbers)
////////////////////////////////////////////////////////////////
#ifndef SERIAL6_TX_BUFFER_SIZE
#define SERIAL6_TX_BUFFER_SIZE 40 // number of outgoing bytes to buffer
#endif
#ifndef SERIAL6_RX_BUFFER_SIZE
#define SERIAL6_RX_BUFFER_SIZE 64 // number of incoming bytes to buffer
#endif
#define RTS_HIGH_WATERMARK (SERIAL6_RX_BUFFER_SIZE-24) // RTS requests sender to pause
#define RTS_LOW_WATERMARK (SERIAL6_RX_BUFFER_SIZE-38) // RTS allows sender to resume
#define IRQ_PRIORITY 64 // 0 = highest priority, 255 = lowest
////////////////////////////////////////////////////////////////
// changes not recommended below this point....
////////////////////////////////////////////////////////////////
#ifdef SERIAL_9BIT_SUPPORT
static uint8_t use9Bits = 0;
#define BUFTYPE uint16_t
#else
#define BUFTYPE uint8_t
#define use9Bits 0
#endif
static volatile BUFTYPE tx_buffer[SERIAL6_TX_BUFFER_SIZE];
static volatile BUFTYPE rx_buffer[SERIAL6_RX_BUFFER_SIZE];
static volatile BUFTYPE *rx_buffer_storage_ = NULL;
static volatile BUFTYPE *tx_buffer_storage_ = NULL;
static size_t tx_buffer_total_size_ = SERIAL6_TX_BUFFER_SIZE;
static size_t rx_buffer_total_size_ = SERIAL6_RX_BUFFER_SIZE;
static size_t rts_low_watermark_ = RTS_LOW_WATERMARK;
static size_t rts_high_watermark_ = RTS_HIGH_WATERMARK;
static volatile uint8_t transmitting = 0;
static volatile uint8_t *transmit_pin=NULL;
#define transmit_assert() *transmit_pin = 1
#define transmit_deassert() *transmit_pin = 0
static volatile uint8_t *rts_pin=NULL;
#define rts_assert() *rts_pin = 0
#define rts_deassert() *rts_pin = 1
#if SERIAL6_TX_BUFFER_SIZE > 65535
static volatile uint32_t tx_buffer_head = 0;
static volatile uint32_t tx_buffer_tail = 0;
#elif SERIAL6_TX_BUFFER_SIZE > 255
static volatile uint16_t tx_buffer_head = 0;
static volatile uint16_t tx_buffer_tail = 0;
#else
static volatile uint8_t tx_buffer_head = 0;
static volatile uint8_t tx_buffer_tail = 0;
#endif
#if SERIAL6_RX_BUFFER_SIZE > 65535
static volatile uint32_t rx_buffer_head = 0;
static volatile uint32_t rx_buffer_tail = 0;
#elif SERIAL6_RX_BUFFER_SIZE > 255
static volatile uint16_t rx_buffer_head = 0;
static volatile uint16_t rx_buffer_tail = 0;
#else
static volatile uint8_t rx_buffer_head = 0;
static volatile uint8_t rx_buffer_tail = 0;
#endif
static uint8_t tx_pin_num = 48;
// UART0 and UART1 are clocked by F_CPU, UART2 is clocked by F_BUS
// UART0 has 8 byte fifo, UART1 and UART2 have 1 byte buffer
#define C2_ENABLE UART_C2_TE | UART_C2_RE | UART_C2_RIE
#define C2_TX_ACTIVE C2_ENABLE | UART_C2_TIE
#define C2_TX_COMPLETING C2_ENABLE | UART_C2_TCIE
#define C2_TX_INACTIVE C2_ENABLE
// BITBAND Support
#define GPIO_BITBAND_ADDR(reg, bit) (((uint32_t)&(reg) - 0x40000000) * 32 + (bit) * 4 + 0x42000000)
#define GPIO_BITBAND_PTR(reg, bit) ((uint32_t *)GPIO_BITBAND_ADDR((reg), (bit)))
#define C3_TXDIR_BIT 5
void serial6_begin(uint32_t divisor)
{
SIM_SCGC1 |= SIM_SCGC1_UART5; // turn on clock, TODO: use bitband
rx_buffer_head = 0;
rx_buffer_tail = 0;
tx_buffer_head = 0;
tx_buffer_tail = 0;
transmitting = 0;
CORE_PIN47_CONFIG = PORT_PCR_PE | PORT_PCR_PS | PORT_PCR_PFE | PORT_PCR_MUX(3);
CORE_PIN48_CONFIG = PORT_PCR_DSE | PORT_PCR_SRE | PORT_PCR_MUX(3);
if (divisor < 32) divisor = 32;
UART5_BDH = (divisor >> 13) & 0x1F;
UART5_BDL = (divisor >> 5) & 0xFF;
UART5_C4 = divisor & 0x1F;
UART5_C1 = 0;
UART5_PFIFO = 0;
UART5_C2 = C2_TX_INACTIVE;
NVIC_SET_PRIORITY(IRQ_UART5_STATUS, IRQ_PRIORITY);
NVIC_ENABLE_IRQ(IRQ_UART5_STATUS);
}
void serial6_format(uint32_t format)
{
uint8_t c;
c = UART5_C1;
c = (c & ~0x13) | (format & 0x03); // configure parity
if (format & 0x04) c |= 0x10; // 9 bits (might include parity)
UART5_C1 = c;
if ((format & 0x0F) == 0x04) UART5_C3 |= 0x40; // 8N2 is 9 bit with 9th bit always 1
c = UART5_S2 & ~0x10;
if (format & 0x10) c |= 0x10; // rx invert
UART5_S2 = c;
c = UART5_C3 & ~0x10;
if (format & 0x20) c |= 0x10; // tx invert
UART5_C3 = c;
#ifdef SERIAL_9BIT_SUPPORT
c = UART5_C4 & 0x1F;
if (format & 0x08) c |= 0x20; // 9 bit mode with parity (requires 10 bits)
UART5_C4 = c;
use9Bits = format & 0x80;
#endif
// For T3.5 See about turning on 2 stop bit mode
if ( format & 0x100) {
uint8_t bdl = UART5_BDL;
UART5_BDH |= UART_BDH_SBNS; // Turn on 2 stop bits - was turned off by set baud
UART5_BDL = bdl; // Says BDH not acted on until BDL is written
}
// process request for half duplex.
if ((format & SERIAL_HALF_DUPLEX) != 0) {
UART5_C1 |= UART_C1_LOOPS | UART_C1_RSRC;
volatile uint32_t *reg = portConfigRegister(tx_pin_num);
*reg = PORT_PCR_DSE | PORT_PCR_SRE | PORT_PCR_MUX(3) | PORT_PCR_PE | PORT_PCR_PS; // pullup on output pin;
// Lets try to make use of bitband address to set the direction for ue...
transmit_pin = (uint8_t*)GPIO_BITBAND_PTR(UART5_C3, C3_TXDIR_BIT);
} else {
if (transmit_pin == (uint8_t*)GPIO_BITBAND_PTR(UART5_C3, C3_TXDIR_BIT)) transmit_pin = NULL;
}
}
void serial6_end(void)
{
if (!(SIM_SCGC1 & SIM_SCGC1_UART5)) return;
while (transmitting) yield(); // wait for buffered data to send
NVIC_DISABLE_IRQ(IRQ_UART5_STATUS);
UART5_C2 = 0;
CORE_PIN47_CONFIG = PORT_PCR_PE | PORT_PCR_PS | PORT_PCR_MUX(1);
CORE_PIN48_CONFIG = PORT_PCR_PE | PORT_PCR_PS | PORT_PCR_MUX(1);
UART5_S1;
UART5_D; // clear leftover error status
rx_buffer_head = 0;
rx_buffer_tail = 0;
if (rts_pin) rts_deassert();
}
void serial6_set_transmit_pin(uint8_t pin)
{
while (transmitting) ;
pinMode(pin, OUTPUT);
digitalWrite(pin, LOW);
transmit_pin = portOutputRegister(pin);
}
void serial6_set_tx(uint8_t pin, uint8_t opendrain)
{
uint32_t cfg;
if (opendrain) pin |= 128;
if (pin == tx_pin_num) return;
if ((SIM_SCGC1 & SIM_SCGC1_UART5)) {
switch (tx_pin_num & 127) {
case 48: CORE_PIN48_CONFIG = 0; break; // PTE24
}
if (opendrain) {
cfg = PORT_PCR_DSE | PORT_PCR_ODE;
} else {
cfg = PORT_PCR_DSE | PORT_PCR_SRE;
}
switch (pin & 127) {
case 48: CORE_PIN48_CONFIG = cfg | PORT_PCR_MUX(3); break;
}
}
tx_pin_num = pin;
}
void serial6_set_rx(uint8_t pin)
{
}
int serial6_set_rts(uint8_t pin)
{
if (!(SIM_SCGC1 & SIM_SCGC1_UART5)) return 0;
if (pin < CORE_NUM_DIGITAL) {
rts_pin = portOutputRegister(pin);
pinMode(pin, OUTPUT);
rts_assert();
} else {
rts_pin = NULL;
return 0;
}
return 1;
}
int serial6_set_cts(uint8_t pin)
{
if (!(SIM_SCGC1 & SIM_SCGC1_UART5)) return 0;
if (pin == 56) {
CORE_PIN56_CONFIG = PORT_PCR_MUX(3) | PORT_PCR_PE; // weak pulldown
} else {
UART5_MODEM &= ~UART_MODEM_TXCTSE;
return 0;
}
UART5_MODEM |= UART_MODEM_TXCTSE;
return 1;
}
void serial6_putchar(uint32_t c)
{
uint32_t head, n;
if (!(SIM_SCGC1 & SIM_SCGC1_UART5)) return;
if (transmit_pin) transmit_assert();
head = tx_buffer_head;
if (++head >= tx_buffer_total_size_) head = 0;
while (tx_buffer_tail == head) {
int priority = nvic_execution_priority();
if (priority <= IRQ_PRIORITY) {
if ((UART5_S1 & UART_S1_TDRE)) {
uint32_t tail = tx_buffer_tail;
if (++tail >= tx_buffer_total_size_) tail = 0;
if (tail < SERIAL6_TX_BUFFER_SIZE) {
n = tx_buffer[tail];
} else {
n = tx_buffer_storage_[tail-SERIAL6_TX_BUFFER_SIZE];
}
if (use9Bits) UART5_C3 = (UART5_C3 & ~0x40) | ((n & 0x100) >> 2);
UART5_D = n;
tx_buffer_tail = tail;
}
} else if (priority >= 256) {
yield(); // wait
}
}
if (head < SERIAL6_TX_BUFFER_SIZE) {
tx_buffer[head] = c;
} else {
tx_buffer_storage_[head - SERIAL6_TX_BUFFER_SIZE] = c;
}
transmitting = 1;
tx_buffer_head = head;
UART5_C2 = C2_TX_ACTIVE;
}
void serial6_write(const void *buf, unsigned int count)
{
const uint8_t *p = (const uint8_t *)buf;
while (count-- > 0) serial6_putchar(*p++);
}
void serial6_flush(void)
{
while (transmitting) yield(); // wait
}
int serial6_write_buffer_free(void)
{
uint32_t head, tail;
head = tx_buffer_head;
tail = tx_buffer_tail;
if (head >= tail) return tx_buffer_total_size_ - 1 - head + tail;
return tail - head - 1;
}
int serial6_available(void)
{
uint32_t head, tail;
head = rx_buffer_head;
tail = rx_buffer_tail;
if (head >= tail) return head - tail;
return rx_buffer_total_size_ + head - tail;
}
int serial6_getchar(void)
{
uint32_t head, tail;
int c;
head = rx_buffer_head;
tail = rx_buffer_tail;
if (head == tail) return -1;
if (++tail >= rx_buffer_total_size_) tail = 0;
if (tail < SERIAL6_RX_BUFFER_SIZE) {
c = rx_buffer[tail];
} else {
c = rx_buffer_storage_[tail-SERIAL6_RX_BUFFER_SIZE];
}
rx_buffer_tail = tail;
if (rts_pin) {
int avail;
if (head >= tail) avail = head - tail;
else avail = rx_buffer_total_size_ + head - tail;
if (avail <= rts_low_watermark_) rts_assert();
}
return c;
}
int serial6_peek(void)
{
uint32_t head, tail;
head = rx_buffer_head;
tail = rx_buffer_tail;
if (head == tail) return -1;
if (++tail >= rx_buffer_total_size_) tail = 0;
if (tail < SERIAL6_RX_BUFFER_SIZE) {
return rx_buffer[tail];
}
return rx_buffer_storage_[tail-SERIAL6_RX_BUFFER_SIZE];
}
void serial6_clear(void)
{
rx_buffer_head = rx_buffer_tail;
if (rts_pin) rts_assert();
}
// status interrupt combines
// Transmit data below watermark UART_S1_TDRE
// Transmit complete UART_S1_TC
// Idle line UART_S1_IDLE
// Receive data above watermark UART_S1_RDRF
// LIN break detect UART_S2_LBKDIF
// RxD pin active edge UART_S2_RXEDGIF
void uart5_status_isr(void)
{
uint32_t head, tail, n;
uint8_t c;
if (UART5_S1 & UART_S1_RDRF) {
if (use9Bits && (UART5_C3 & 0x80)) {
n = UART5_D | 0x100;
} else {
n = UART5_D;
}
head = rx_buffer_head + 1;
if (head >= rx_buffer_total_size_) head = 0;
if (head != rx_buffer_tail) {
if (head < SERIAL6_RX_BUFFER_SIZE) {
rx_buffer[head] = n;
} else {
rx_buffer_storage_[head-SERIAL6_RX_BUFFER_SIZE] = n;
}
rx_buffer_head = head;
}
if (rts_pin) {
int avail;
tail = tx_buffer_tail;
if (head >= tail) avail = head - tail;
else avail = rx_buffer_total_size_ + head - tail;
if (avail >= rts_high_watermark_) rts_deassert();
}
}
c = UART5_C2;
if ((c & UART_C2_TIE) && (UART5_S1 & UART_S1_TDRE)) {
head = tx_buffer_head;
tail = tx_buffer_tail;
if (head == tail) {
UART5_C2 = C2_TX_COMPLETING;
} else {
if (++tail >= tx_buffer_total_size_) tail = 0;
if (tail < SERIAL6_TX_BUFFER_SIZE) {
n = tx_buffer[tail];
} else {
n = tx_buffer_storage_[tail-SERIAL6_TX_BUFFER_SIZE];
}
if (use9Bits) UART5_C3 = (UART5_C3 & ~0x40) | ((n & 0x100) >> 2);
UART5_D = n;
tx_buffer_tail = tail;
}
}
if ((c & UART_C2_TCIE) && (UART5_S1 & UART_S1_TC)) {
transmitting = 0;
if (transmit_pin) transmit_deassert();
UART5_C2 = C2_TX_INACTIVE;
}
}
void serial6_add_memory_for_read(void *buffer, size_t length)
{
rx_buffer_storage_ = (BUFTYPE*)buffer;
if (buffer) {
rx_buffer_total_size_ = SERIAL6_RX_BUFFER_SIZE + length;
} else {
rx_buffer_total_size_ = SERIAL6_RX_BUFFER_SIZE;
}
rts_low_watermark_ = RTS_LOW_WATERMARK + length;
rts_high_watermark_ = RTS_HIGH_WATERMARK + length;
}
void serial6_add_memory_for_write(void *buffer, size_t length)
{
tx_buffer_storage_ = (BUFTYPE*)buffer;
if (buffer) {
tx_buffer_total_size_ = SERIAL6_TX_BUFFER_SIZE + length;
} else {
tx_buffer_total_size_ = SERIAL6_TX_BUFFER_SIZE;
}
}
#endif // HAS_KINETISK_UART5