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-rw-r--r--stm32/app/1wire.c392
1 files changed, 0 insertions, 392 deletions
diff --git a/stm32/app/1wire.c b/stm32/app/1wire.c
deleted file mode 100644
index c374c5c..0000000
--- a/stm32/app/1wire.c
+++ /dev/null
@@ -1,392 +0,0 @@
-#include "project.h"
-
-#define USART2_TX GPIO_USART2_TX
-#define USART2_TX_PORT GPIOA
-
-#define BIT_ZERO '0'
-#define BIT_ONE '1'
-#define BIT_UNKNOWN 'U'
-#define BIT_CONFLICT 'C'
-
-
-static int poke;
-static volatile unsigned exchange_timeout;
-
-void onewire_tick (void)
-{
- static unsigned ticker;
-
- if (exchange_timeout)
- exchange_timeout--;
-
-
- ticker++;
-
- if (ticker < MS_TO_TICKS (5000))
- return;
-
- ticker = 0;
- poke = 1;
-
-
-}
-
-
-static unsigned usart_send_ready (uint32_t usart)
-{
- return (USART_SR (usart) & USART_SR_TXE);
-}
-
-
-static unsigned usart_recv_ready (uint32_t usart)
-{
- return (USART_SR (usart) & USART_SR_RXNE);
-}
-
-
-
-static int onewire_exchange (int tx, unsigned timeout)
-{
- int rx;
- (void) USART_SR (USART2);
- (void) usart_recv (USART2);
-
-
- exchange_timeout = MS_TO_TICKS (timeout);
-
- while (!usart_send_ready (USART2))
- if (!exchange_timeout)
- return -1;
-
- usart_send (USART2, tx);
-
- exchange_timeout = MS_TO_TICKS (timeout);
-
- while (!usart_recv_ready (USART2))
- if (!exchange_timeout)
- return -1;
-
-
- rx = usart_recv (USART2);
-
- return rx;
-
-}
-
-/* returns 1 if nothing on bus or error */
-int
-onewire_reset (void)
-{
- int ret;
-
- usart_set_baudrate (USART2, 9600);
- delay_ms (1);
- ret = onewire_exchange (0xf0, 60);
- usart_set_baudrate (USART2, 115200);
- delay_ms (1);
-
- return (ret == 0xf0);
-}
-
-static void
-onewire_one (void)
-{
- onewire_exchange (0xff, 3);
-}
-
-static void
-onewire_zero (void)
-{
- onewire_exchange (0x00, 3);
-}
-
-static int
-onewire_read (void)
-{
- uint8_t rx;
-
- rx = onewire_exchange (0xff, 3);
-
- return (rx == 0xff);
-}
-
-
-void
-onewire_write_byte (uint8_t v)
-{
- int c;
-
-
- for (c = 0; c < 8; ++c) {
- if (v & 1)
- onewire_one();
- else
- onewire_zero();
-
- v >>= 1;
- }
-}
-
-uint8_t
-onewire_read_byte (void)
-{
- uint8_t v = 0;
- int c;
-
-
- for (c = 0; c < 8; ++c) {
- v >>= 1;
-
- if (onewire_read())
- v |= 0x80;
- }
-
-
- return v;
-}
-
-
-
-void
-onewire_read_bytes (uint8_t *buf, int n)
-{
- while (n--)
- * (buf++) = onewire_read_byte();
-}
-
-
-void
-onewire_write_bytes (const uint8_t *buf, int n)
-{
- while (n--)
- onewire_write_byte (* (buf++));
-}
-
-
-int onewire_select (const Onewire_addr *a)
-{
- if (!a)
- onewire_write_byte (ONEWIRE_SKIP_ROM);
- else {
- onewire_write_byte (ONEWIRE_MATCH_ROM);
- onewire_write_bytes (a->a, 8);
- }
-
- return 0;
-}
-
-
-int onewire_reset_and_select (const Onewire_addr *a)
-{
- if (onewire_reset())
- return 1;
-
- if (onewire_select (a))
- return 1;
-
- return 0;
-}
-
-
-
-int onewire_wait_complete (unsigned timeout)
-{
- while (! (onewire_read())) {
- delay_ms (10);
-
- if (! (timeout--))
- return 1;
- }
-
- return 0;
-}
-
-
-
-int
-onewire_check_crc (uint8_t *buf, int n, uint8_t v)
-{
- uint8_t crc = 0;
- int i;
-
- while (n--) {
- uint8_t v = * (buf++);
-
- for (i = 0; i < 8; ++i) {
- uint8_t mix = (crc ^ v) & 0x01;
- crc >>= 1;
-
- if (mix)
- crc ^= 0x8C;
-
- v >>= 1;
- }
- }
-
- return ! (crc == v);
-
-}
-
-static int onewire_conduct_search (uint8_t *bits)
-{
- unsigned i, ir, r;
-
- if (onewire_reset())
- return -1;
-
- onewire_write_byte (ONEWIRE_SEARCH_ROM);
-
-
- for (i = 0; i < 64; ++i) {
-
- r = onewire_read();
- ir = onewire_read();
-
-#if 0
-
- if ((i == 27) || (i == 24) || (i == 39))
- ir = r = 0;
-
-#endif
-
- switch (bits[i]) {
- case BIT_UNKNOWN:
-
- if (!r && ir) { /* Zero */
- bits[i] = BIT_ZERO;
- onewire_zero();
- } else if (r && !ir) { /*One */
- bits[i] = BIT_ONE;
- onewire_one();
- } else if (r && ir) { /*Nothing here */
- //MEH;
- return -1;
- } else if (!r && !ir) { /*Both */
- bits[i] = BIT_CONFLICT;
- onewire_zero();
- }
-
- break;
-
- case BIT_CONFLICT:
- if (!r && !ir) /*Both */
- onewire_zero();
- else {
- //MEH;
- return -1;
- }
-
- break;
-
- case BIT_ZERO:
- if (!r)
- onewire_zero();
- else {
- //MEH;
- return -1;
- }
-
- break;
-
- case BIT_ONE:
- if (!ir)
- onewire_one();
- else {
- //MEH;
- return -1;
- }
-
- break;
- }
- }
-
- return 0;
-}
-
-static int onewire_next (uint8_t *bits)
-{
- unsigned i;
-
- for (i = 0; i < 64; ++i) {
-
- if (bits[63 - i] == BIT_CONFLICT) {
- bits[63 - i] = BIT_ONE;
- return 1;
- }
-
- bits[63 - i] = BIT_UNKNOWN;
- }
-
- return 0;
-}
-
-static void onewire_bits_to_a (uint8_t *bits, Onewire_addr *a)
-{
- unsigned i, j, c;
-
- for (i = 0, j = 0; i < 8; ++i) {
-
- a->a[i] = 0;
-
- for (c = 1; c < 0x100; c <<= 1, ++j) {
- if (bits[j] == BIT_ONE)
- a->a[i] |= c;
- }
- }
-}
-
-int onewire_search (void)
-{
- uint8_t bits[64];
- Onewire_addr a;
- int r, c;
-
- delay_ms (2000);
-
- memset (bits, BIT_UNKNOWN, sizeof (bits));
-
- do {
- r = onewire_conduct_search (bits);
-
- if (!r) {
- onewire_bits_to_a (bits, &a);
- c = onewire_check_crc (&a.a[0], 7, a.a[7]);
-
- if (!c) {
- printf ("QO: {0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x,0x%02x}\r\n",
- a.a[0],
- a.a[1],
- a.a[2],
- a.a[3],
- a.a[4],
- a.a[5],
- a.a[6],
- a.a[7]);
- }
-
- }
-
- } while (onewire_next (bits));
-
-
- return 0;
-}
-
-
-
-void
-onewire_init (void)
-{
- MAP_AF_OD (USART2_TX);
-
- usart_set_baudrate (USART2, 115200);
- usart_set_databits (USART2, 8);
- usart_set_stopbits (USART2, USART_STOPBITS_1);
- usart_set_parity (USART2, USART_PARITY_NONE);
- usart_set_flow_control (USART2, USART_FLOWCONTROL_NONE);
- usart_set_mode (USART2, USART_MODE_TX_RX);
-
- USART_CR3 (USART2) |= USART_CR3_HDSEL;
-
- usart_enable (USART2);
-}
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