| | | The Canon driver reference | |
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#include <serial.h> int canon_serial_change_speed (GPPort *gdev, int speed); unsigned char* canon_serial_dialogue (Camera *camera, GPContext *context, unsigned char mtype, unsigned char dir, int *len, ...); void canon_serial_error_type (Camera *camera); int canon_serial_get_byte (GPPort *gdev); int canon_serial_get_cts (GPPort *gdev); int canon_serial_get_dirents (Camera *camera, unsigned char **dirent_data, unsigned int *dirents_length, const char *path, GPContext *context); unsigned char* canon_serial_get_file (Camera *camera, const char *name, int *length, GPContext *context); int canon_serial_get_thumbnail (Camera *camera, const char *name, unsigned char **data, int *length, GPContext *context); int canon_serial_init (Camera *camera); int canon_serial_put_file (Camera *camera, CameraFile *file, char *destname, char *destpath, GPContext *context); int canon_serial_ready (Camera *camera, GPContext *context); unsigned char* canon_serial_recv_frame (Camera *camera, int *len); unsigned char* canon_serial_recv_msg (Camera *camera, unsigned char mtype, unsigned char dir, int *total, GPContext *context); unsigned char* canon_serial_recv_packet (Camera *camera, unsigned char *type, unsigned char *seq, int *len); int canon_serial_send (Camera *camera, unsigned char *buf, int len, int sleep); int canon_serial_send_frame (Camera *camera, unsigned char *pkt, int len); int canon_serial_send_packet (Camera *camera, unsigned char type, unsigned char seq, unsigned char *pkt, int len); int canon_serial_wait_for_ack (Camera *camera); int canon_psa50_chk_crc (unsigned char *pkt, int len, unsigned short crc); unsigned short canon_psa50_gen_crc (unsigned char *pkt, int len); void serial_flush_input (GPPort *gdev); void serial_flush_output (GPPort *gdev); void serial_set_timeout (GPPort *gdev, int to); #define MAX_TRIES #define USLEEP1 #define USLEEP2 #define HDR_FIXED_LEN #define DATA_BLOCK #define ERROR_ADDRESSED #define ERROR_LOWBATT #define ERROR_RECEIVED #define FATAL_ERROR #define NOERROR #define CANON_FBEG #define CANON_FEND #define CANON_ESC #define CANON_XOR #define MAX_PKT_PAYLOAD #define PKT_HDR_LEN #define PKT_SEQ #define PKT_TYPE #define PKT_LEN_LSB #define PKT_LEN_MSB #define PKT_MSG #define PKT_EOT #define PKT_ACK #define PKT_NACK #define PKTACK_NACK #define PKT_UPLOAD_EOT #define MAX_MSG_SIZE #define MSG_HDR_LEN #define MSG_02 #define MSG_MTYPE #define MSG_DIR #define MSG_LEN_LSB #define MSG_LEN_MSB #define DIR_REVERSE #define UPLOAD_DATA_BLOCK #define SPEED_9600 #define SPEED_19200 #define SPEED_38400 #define SPEED_57600 #define SPEED_115200 #define MAX_PKT_SIZE #define FRAG_NUM #define FRAG_LEN_LSB #define FRAG_LEN_MSB
int canon_serial_change_speed (GPPort *gdev, int speed);
Changes the speed of the communication.
| gdev : | serial port to use |
| speed : | the new speed |
| Returns : | 1 on success. 0 on any error. |
unsigned char* canon_serial_dialogue (Camera *camera,
GPContext *context,
unsigned char mtype,
unsigned char dir,
int *len,
...);Higher level function: sends a message and waits for a reply from the camera.
Payload: each argument after "len" goes by 2: the variable itself, and the next argument has to be its length. You also have to finish the list by a "NULL".
Example: To send a string called "name" : canon_serial_dialogue(0x05,0x12,&len,name,strlen(name)+1,NULL);
| camera : | camera with which to communicate |
| context : | context for error reporting |
| mtype : | type |
| dir : | direction |
| len : | length of the received payload |
| ... : | The rest of the arguments will be put together to fill up the payload of the request message. |
| Returns : | buffer received from canon_serial_recv_msg(), NULL if failure |
void canon_serial_error_type (Camera *camera);
logs a debug message corresponding to the error encountered
| camera : | Camera object to work with |
int canon_serial_get_byte (GPPort *gdev);
Gets the next byte from the serial line. Actually the function reads chunks of data and keeps them in a cache. Only one byte per call will be returned.
| gdev : | serial port to use |
| Returns : | the byte on success, -1 on error. |
int canon_serial_get_cts (GPPort *gdev);
Gets the status of the CTS (Clear To Send) line on the serial port.
CTS is "1" when the camera is ON, and "0" when it is OFF.
| gdev : | serial port to use |
| Returns : | 1 on CTS high. 0 on CTS low. |
int canon_serial_get_dirents (Camera *camera,
unsigned char **dirent_data,
unsigned int *dirents_length,
const char *path,
GPContext *context);Lists a directory.
| camera : | camera to initialize |
| dirent_data : | to receive directory data |
| dirents_length : | to receive length of dirent_data |
| path : | pathname of directory to list |
| context : | context for error reporting |
| Returns : | gphoto2 error code |
unsigned char* canon_serial_get_file (Camera *camera,
const char *name,
int *length,
GPContext *context);Get a file from a USB_connected Canon camera.
| camera : | camera to lock keys on |
| name : | name of file to fetch |
| length : | to receive length of image data |
| context : | context for error reporting |
| Returns : | buffer containing file data (or NULL on failure); length in length. |
int canon_serial_get_thumbnail (Camera *camera,
const char *name,
unsigned char **data,
int *length,
GPContext *context);This is just the serial specific part extracted from the older canon_get_thumbnail() routine.
| camera : | camera to work on |
| name : | file name (complete canon path) of file to get thumbnail for |
| data : | pointer to data pointer |
| length : | pointer to data length |
| context : | context for error reporting |
| Returns : | gphoto2 error code |
int canon_serial_init (Camera *camera);
Initializes the given serial device by setting speed, parity, etc.
| camera : | Camera object to initialize |
| Returns : | GP_OK |
int canon_serial_put_file (Camera *camera,
CameraFile *file,
char *destname,
char *destpath,
GPContext *context);Uploads file to camera via serial port
| camera : | Camera object to work with |
| file : | CameraFile object to upload |
| destname : | name file should have on camera |
| destpath : | pathname for directory to put file |
| context : | context for error reporting |
| Returns : | gphoto2 error code |
int canon_serial_ready (Camera *camera,
GPContext *context);serial part of canon_int_ready
| camera : | camera to get ready |
| context : | context for error reporting |
| Returns : | gphoto2 error code |
unsigned char* canon_serial_recv_frame (Camera *camera,
int *len);Receive a frame from the camera
| camera : | Camera object to work with |
| len : | to receive the length of the buffer |
| Returns : | a buffer containing a frame from the camera, or NULL on error. On success, len will contain the length of the buffer. |
unsigned char* canon_serial_recv_msg (Camera *camera,
unsigned char mtype,
unsigned char dir,
int *total,
GPContext *context);Receives a message from the camera.
See the "Protocol" file for an explanation of the various elements needed to handle a message.
| camera : | Camera object to work with |
| mtype : | message type. |
| dir : | direction. |
| total : | payload length (set by this function). |
| context : | context for error reporting |
| Returns : | char* pointer to the message payload; NULL on failure. |
unsigned char* canon_serial_recv_packet (Camera *camera,
unsigned char *type,
unsigned char *seq,
int *len);Receives a packet from the serial port using canon_serial_send_frame(), decodes frame information (type, sequence number, and length), and returns it stripped of frame information.
| camera : | Camera object to work with |
| type : | Type of packet |
| seq : | Sequence number of packet |
| len : | length of data received |
| Returns : | packet data (or NULL if failure). Type in type, sequence number in seq, and length in len. |
int canon_serial_send (Camera *camera,
unsigned char *buf,
int len,
int sleep);Send the given buffer with given length over the serial line.
| camera : | Camera object to work with |
| buf : | the raw data buffer to send |
| len : | the length of the buffer |
| sleep : | time in usec to wait between characters |
| Returns : | 0 on success, -1 on error. |
int canon_serial_send_frame (Camera *camera,
unsigned char *pkt,
int len);Sends a frame of data to camera
| camera : | Camera object to work with |
| pkt : | Data to send to camera |
| len : | Length of packet |
| Returns : | 1 if canon_serial_send() succeeds, 0 if it fails |
int canon_serial_send_packet (Camera *camera,
unsigned char type,
unsigned char seq,
unsigned char *pkt,
int len);frames a packet (generates CRC, packs with sequence number and length) and sends it to the camera through the serial port using canon_serial_send_frame().
| camera : | Camera object to work with |
| type : |
|
| seq : |
|
| pkt : | data to send to camera |
| len : | length of data |
| Returns : | status from canon_serial_send_frame() |
int canon_serial_wait_for_ack (Camera *camera);
Waits for an "ACK" from the camera.
| camera : | Camera object to work with |
| Returns : | 1 : ACK received 0 : communication error (no reply received for example) -1 : NACK received. |
int canon_psa50_chk_crc (unsigned char *pkt,
int len,
unsigned short crc);Calculate a new checksum for the packet and compare it with an existing checksum to detect transmission errors.
| pkt : | packet |
| len : | length of pkt |
| Param3 : | |
| Returns : | 1 on success or if checksum calculation would fail 0 if checksums don't match |
unsigned short canon_psa50_gen_crc (unsigned char *pkt,
int len);Calculate a CRC on a Canon packet
| pkt : | packet data on which to calculate checksum |
| len : | length of pkt |
| Returns : | CRC value. On error doesn't return at all but exits program with a message to stderr. |
void serial_flush_input (GPPort *gdev);
Dummy function.
| gdev : | serial port to use |
void serial_flush_output (GPPort *gdev);
Dummy function.
| gdev : | serial port to use |
void serial_set_timeout (GPPort *gdev, int to);
Sets the timeout, in miliseconds.
| gdev : | serial port to use |
| to : | timeout in milliseconds |
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