libdc/src/oceanic_atom2.c

380 lines
11 KiB
C

#include <string.h> // memcpy
#include <stdlib.h> // malloc, free
#include <assert.h> // assert
#include "oceanic.h"
#include "serial.h"
#include "utils.h"
#include "ringbuffer.h"
#define MAXRETRIES 2
#define WARNING(expr) \
{ \
message ("%s:%d: %s\n", __FILE__, __LINE__, expr); \
}
#define RB_LOGBOOK_EMPTY 0x0230
#define RB_LOGBOOK_BEGIN 0x0240
#define RB_LOGBOOK_END 0x0A40
#define RB_LOGBOOK_DISTANCE(a,b) ringbuffer_distance (a, b, RB_LOGBOOK_BEGIN, RB_LOGBOOK_END)
#define RB_PROFILE_EMPTY 0x0A40
#define RB_PROFILE_BEGIN 0x0A50
#define RB_PROFILE_END 0xFFF0
#define RB_PROFILE_DISTANCE(a,b) ringbuffer_distance (a, b, RB_PROFILE_BEGIN, RB_PROFILE_END)
#define PT_LOGBOOK_FIRST(x) ( (x)[4] + ((x)[5] << 8) )
#define PT_LOGBOOK_LAST(x) ( (x)[6] + ((x)[7] << 8) )
#define PT_PROFILE_FIRST(x) ( (x)[5] + (((x)[6] & 0x0F) << 8) )
#define PT_PROFILE_LAST(x) ( ((x)[6] >> 4) + ((x)[7] << 4) )
struct atom2 {
struct serial *port;
};
static unsigned char
oceanic_atom2_checksum (const unsigned char data[], unsigned int size, unsigned char init)
{
unsigned char crc = init;
for (unsigned int i = 0; i < size; ++i)
crc += data[i];
return crc;
}
static int
oceanic_atom2_send (atom2 *device, const unsigned char command[], unsigned int csize)
{
// Send the command to the dive computer and
// wait until all data has been transmitted.
serial_write (device->port, command, csize);
serial_drain (device->port);
return OCEANIC_SUCCESS;
}
static int
oceanic_atom2_transfer (atom2 *device, const unsigned char command[], unsigned int csize, unsigned char answer[], unsigned int asize, int handshake)
{
assert (asize >= 2);
// Occasionally, the dive computer does not respond to a command.
// In that case we retry the command a number of times before
// returning an error. Usually the dive computer will respond
// again during one of the retries.
for (unsigned int i = 0;; ++i) {
// Send the command to the dive computer.
int rc = oceanic_atom2_send (device, command, csize);
if (rc != OCEANIC_SUCCESS) {
WARNING ("Failed to send the command.");
return rc;
}
// Receive the answer of the dive computer.
rc = serial_read (device->port, answer, asize);
if (rc != asize) {
WARNING ("Failed to receive the answer.");
if (rc == -1)
return OCEANIC_ERROR_IO;
if (i < MAXRETRIES)
continue; // Retry.
return OCEANIC_ERROR_TIMEOUT;
}
// Verify the header of the package.
unsigned char header = (handshake ? 0xA5 : 0x5A);
if (answer[0] != header) {
WARNING ("Unexpected answer start byte(s).");
return OCEANIC_ERROR_PROTOCOL;
}
// Verify the checksum of the package.
unsigned char crc = answer[asize - 1];
unsigned char ccrc = oceanic_atom2_checksum (answer + 1, asize - 2, 0x00);
if (crc != ccrc) {
WARNING ("Unexpected answer CRC.");
return OCEANIC_ERROR_PROTOCOL;
}
return OCEANIC_SUCCESS;
}
}
int
oceanic_atom2_open (atom2 **out, const char* name)
{
if (out == NULL)
return OCEANIC_ERROR;
// Allocate memory.
struct atom2 *device = malloc (sizeof (struct atom2));
if (device == NULL) {
WARNING ("Failed to allocate memory.");
return OCEANIC_ERROR_MEMORY;
}
// Set the default values.
device->port = NULL;
// Open the device.
int rc = serial_open (&device->port, name);
if (rc == -1) {
WARNING ("Failed to open the serial port.");
free (device);
return OCEANIC_ERROR_IO;
}
// Set the serial communication protocol (38400 8N1).
rc = serial_configure (device->port, 38400, 8, SERIAL_PARITY_NONE, 1, SERIAL_FLOWCONTROL_NONE);
if (rc == -1) {
WARNING ("Failed to set the terminal attributes.");
serial_close (device->port);
free (device);
return OCEANIC_ERROR_IO;
}
// Set the timeout for receiving data (3000 ms).
if (serial_set_timeout (device->port, 3000) == -1) {
WARNING ("Failed to set the timeout.");
serial_close (device->port);
free (device);
return OCEANIC_ERROR_IO;
}
// Give the interface 100 ms to settle and draw power up.
serial_sleep (100);
// Make sure everything is in a sane state.
serial_flush (device->port, SERIAL_QUEUE_BOTH);
// Send the handshake to connect to the device.
unsigned char answer[3] = {0};
unsigned char command[3] = {0xA8, 0x99, 0x00};
rc = oceanic_atom2_transfer (device, command, sizeof (command), answer, sizeof (answer), 1);
if (rc != OCEANIC_SUCCESS) {
serial_close (device->port);
free (device);
return rc;
}
// Verify the handshake.
if (answer[1] != 0xA5) {
WARNING ("Unexpected handshake byte(s).");
serial_close (device->port);
free (device);
return OCEANIC_ERROR_PROTOCOL;
}
*out = device;
return OCEANIC_SUCCESS;
}
int
oceanic_atom2_close (atom2 *device)
{
if (device == NULL)
return OCEANIC_SUCCESS;
// Close the device.
if (serial_close (device->port) == -1) {
free (device);
return OCEANIC_ERROR_IO;
}
// Free memory.
free (device);
return OCEANIC_SUCCESS;
}
int
oceanic_atom2_read_version (atom2 *device, unsigned char data[], unsigned int size)
{
if (device == NULL)
return OCEANIC_ERROR;
if (size < OCEANIC_ATOM2_PACKET_SIZE)
return OCEANIC_ERROR_MEMORY;
unsigned char answer[OCEANIC_ATOM2_PACKET_SIZE + 2] = {0};
unsigned char command[2] = {0x84, 0x00};
int rc = oceanic_atom2_transfer (device, command, sizeof (command), answer, sizeof (answer), 0);
if (rc != OCEANIC_SUCCESS)
return rc;
memcpy (data, answer + 1, OCEANIC_ATOM2_PACKET_SIZE);
#ifndef NDEBUG
answer[OCEANIC_ATOM2_PACKET_SIZE + 1] = 0;
message ("ATOM2ReadVersion()=\"%s\"\n", answer + 1);
#endif
return OCEANIC_SUCCESS;
}
int
oceanic_atom2_read_memory (atom2 *device, unsigned int address, unsigned char data[], unsigned int size)
{
if (device == NULL)
return OCEANIC_ERROR;
assert (address % OCEANIC_ATOM2_PACKET_SIZE == 0);
assert (size % OCEANIC_ATOM2_PACKET_SIZE == 0);
// The data transmission is split in packages
// of maximum $OCEANIC_ATOM2_PACKET_SIZE bytes.
unsigned int nbytes = 0;
while (nbytes < size) {
// Read the package.
unsigned int number = address / OCEANIC_ATOM2_PACKET_SIZE;
unsigned char answer[OCEANIC_ATOM2_PACKET_SIZE + 2] = {0};
unsigned char command[4] = {0xB1,
(number >> 8) & 0xFF, // high
(number ) & 0xFF, // low
0};
int rc = oceanic_atom2_transfer (device, command, sizeof (command), answer, sizeof (answer), 0);
if (rc != OCEANIC_SUCCESS)
return rc;
memcpy (data, answer + 1, OCEANIC_ATOM2_PACKET_SIZE);
#ifndef NDEBUG
message ("ATOM2Read(0x%04x,%d)=\"", address, OCEANIC_ATOM2_PACKET_SIZE);
for (unsigned int i = 0; i < OCEANIC_ATOM2_PACKET_SIZE; ++i) {
message("%02x", data[i]);
}
message("\"\n");
#endif
nbytes += OCEANIC_ATOM2_PACKET_SIZE;
address += OCEANIC_ATOM2_PACKET_SIZE;
data += OCEANIC_ATOM2_PACKET_SIZE;
}
return OCEANIC_SUCCESS;
}
static int
oceanic_atom2_read_ringbuffer (atom2 *device, unsigned int address, unsigned char data[], unsigned int size, unsigned int begin, unsigned int end)
{
assert (address >= begin && address < end);
assert (size <= end - begin);
if (address + size > end) {
unsigned int a = end - address;
unsigned int b = size - a;
int rc = oceanic_atom2_read_memory (device, address, data, a);
if (rc != OCEANIC_SUCCESS)
return rc;
rc = oceanic_atom2_read_memory (device, begin, data + a, b);
if (rc != OCEANIC_SUCCESS)
return rc;
} else {
int rc = oceanic_atom2_read_memory (device, address, data, size);
if (rc != OCEANIC_SUCCESS)
return rc;
}
return OCEANIC_SUCCESS;
}
int
oceanic_atom2_read_dives (atom2 *device, dive_callback_t callback, void *userdata)
{
if (device == NULL)
return OCEANIC_ERROR;
// Read the pointer data.
unsigned char pointers[OCEANIC_ATOM2_PACKET_SIZE] = {0};
int rc = oceanic_atom2_read_memory (device, 0x0040, pointers, OCEANIC_ATOM2_PACKET_SIZE);
if (rc != OCEANIC_SUCCESS) {
WARNING ("Cannot read pointers.");
return rc;
}
// Get the logbook pointers.
unsigned int logbook_first = PT_LOGBOOK_FIRST (pointers);
unsigned int logbook_last = PT_LOGBOOK_LAST (pointers);
message ("logbook: first=%04x, last=%04x\n", logbook_first, logbook_last);
// Calculate the total number of logbook entries.
// In a typical ringbuffer implementation (with only two pointers),
// there is no distinction between an empty and a full ringbuffer.
// However, the ATOM2 sets the pointers to a fixed (invalid) value
// to indicate an empty buffer. With this knowledge, we can detect
// the difference between both cases correctly.
if (logbook_first == RB_LOGBOOK_EMPTY && logbook_last == RB_LOGBOOK_EMPTY)
return OCEANIC_SUCCESS;
unsigned int logbook_count = RB_LOGBOOK_DISTANCE (logbook_first, logbook_last) /
(OCEANIC_ATOM2_PACKET_SIZE / 2) + 1;
message ("logbook: count=%u\n", logbook_count);
// Align the pointers to the packet size.
unsigned int logbook_page_offset = logbook_first % OCEANIC_ATOM2_PACKET_SIZE;
unsigned int logbook_page_first = (logbook_first / OCEANIC_ATOM2_PACKET_SIZE) * OCEANIC_ATOM2_PACKET_SIZE;
unsigned int logbook_page_last = (logbook_last / OCEANIC_ATOM2_PACKET_SIZE) * OCEANIC_ATOM2_PACKET_SIZE;
unsigned int logbook_page_len = RB_LOGBOOK_DISTANCE (logbook_page_first, logbook_page_last) + OCEANIC_ATOM2_PACKET_SIZE;
message ("logbook: first=%04x, last=%04x, len=%u, offset=%u\n",
logbook_page_first, logbook_page_last, logbook_page_len, logbook_page_offset);
// Read the logbook data.
unsigned char logbooks[RB_LOGBOOK_END - RB_LOGBOOK_BEGIN] = {0};
rc = oceanic_atom2_read_ringbuffer (device, logbook_page_first, logbooks, logbook_page_len, RB_LOGBOOK_BEGIN, RB_LOGBOOK_END);
if (rc != OCEANIC_SUCCESS) {
WARNING ("Cannot read dive logbooks.");
return rc;
}
// Traverse the logbook ringbuffer backwards to retrieve the most recent
// dives first. The logbook ringbuffer is linearized at this point, so
// we do not have to take into account any memory wrapping near the end
// of the memory buffer.
unsigned char *current = logbooks + logbook_page_offset + (logbook_count - 1) * (OCEANIC_ATOM2_PACKET_SIZE / 2);
for (unsigned int i = 0; i < logbook_count; ++i) {
message ("logbook: index=%u\n", i);
// Get the profile pointers.
unsigned int profile_first = PT_PROFILE_FIRST (current) * OCEANIC_ATOM2_PACKET_SIZE;
unsigned int profile_last = PT_PROFILE_LAST (current) * OCEANIC_ATOM2_PACKET_SIZE;
unsigned int profile_len = RB_PROFILE_DISTANCE (profile_first, profile_last) + OCEANIC_ATOM2_PACKET_SIZE;
message ("profile: first=%04x, last=%04x, len=%u\n", profile_first, profile_last, profile_len);
// Read the profile data.
unsigned char profile[RB_PROFILE_END - RB_PROFILE_BEGIN + 8] = {0};
rc = oceanic_atom2_read_ringbuffer (device, profile_first, profile + 8, profile_len, RB_PROFILE_BEGIN, RB_PROFILE_END);
if (rc != OCEANIC_SUCCESS) {
WARNING ("Cannot read dive profiles.");
return rc;
}
// Copy the logbook data to the profile.
memcpy (profile, current, 8);
if (callback)
callback (profile, profile_len + 8, userdata);
// Advance to the next logbook entry.
current -= (OCEANIC_ATOM2_PACKET_SIZE / 2);
}
return OCEANIC_SUCCESS;
}