Oh, interesting. I didn’t realize one could use the OpenLog in a more autonomous way. I am using the OpenLog as the storage component of the project, with the processing component being the Sparkfun Redboard, and the camera being an Adafruit TTL Serial Camera, which is (I believe) where the image is buffered. So, the main code is living on the redboard/Uno, the camera is taking a photo and buffering it, and then the main code is reading in that buffer and trying to write it out to the OpenLog. The basic “snapshot” example code using the SD library (code from Adafruit), is below, in case the whole script is helpful. Thanks very much!
// This is a basic snapshot sketch using the VC0706 library.
// On start, the Arduino will find the camera and SD card and
// then snap a photo, saving it to the SD card.
// Public domain.
// If using an Arduino Mega (1280, 2560 or ADK) in conjunction
// with an SD card shield designed for conventional Arduinos
// (Uno, etc.), it's necessary to edit the library file:
// libraries/SD/utility/Sd2Card.h
// Look for this line:
// #define MEGA_SOFT_SPI 0
// change to:
// #define MEGA_SOFT_SPI 1
// This is NOT required if using an SD card breakout interfaced
// directly to the SPI bus of the Mega (pins 50-53), or if using
// a non-Mega, Uno-style board.
#include <Adafruit_VC0706.h>
#include <SPI.h>
#include <SD.h>
// comment out this line if using Arduino V23 or earlier
#include <SoftwareSerial.h>
// uncomment this line if using Arduino V23 or earlier
// #include <NewSoftSerial.h>
// SD card chip select line varies among boards/shields:
// Adafruit SD shields and modules: pin 10
// Arduino Ethernet shield: pin 4
// Sparkfun SD shield: pin 8
// Arduino Mega w/hardware SPI: pin 53
// Teensy 2.0: pin 0
// Teensy++ 2.0: pin 20
#define chipSelect 10
// Pins for camera connection are configurable.
// With the Arduino Uno, etc., most pins can be used, except for
// those already in use for the SD card (10 through 13 plus
// chipSelect, if other than pin 10).
// With the Arduino Mega, the choices are a bit more involved:
// 1) You can still use SoftwareSerial and connect the camera to
// a variety of pins...BUT the selection is limited. The TX
// pin from the camera (RX on the Arduino, and the first
// argument to SoftwareSerial()) MUST be one of: 62, 63, 64,
// 65, 66, 67, 68, or 69. If MEGA_SOFT_SPI is set (and using
// a conventional Arduino SD shield), pins 50, 51, 52 and 53
// are also available. The RX pin from the camera (TX on
// Arduino, second argument to SoftwareSerial()) can be any
// pin, again excepting those used by the SD card.
// 2) You can use any of the additional three hardware UARTs on
// the Mega board (labeled as RX1/TX1, RX2/TX2, RX3,TX3),
// but must specifically use the two pins defined by that
// UART; they are not configurable. In this case, pass the
// desired Serial object (rather than a SoftwareSerial
// object) to the VC0706 constructor.
// Using SoftwareSerial (Arduino 1.0+) or NewSoftSerial (Arduino 0023 & prior):
#if ARDUINO >= 100
// On Uno: camera TX connected to pin 2, camera RX to pin 3:
SoftwareSerial cameraconnection = SoftwareSerial(2, 3);
// On Mega: camera TX connected to pin 69 (A15), camera RX to pin 3:
//SoftwareSerial cameraconnection = SoftwareSerial(69, 3);
#else
NewSoftSerial cameraconnection = NewSoftSerial(2, 3);
#endif
Adafruit_VC0706 cam = Adafruit_VC0706(&cameraconnection);
// Using hardware serial on Mega: camera TX conn. to RX1,
// camera RX to TX1, no SoftwareSerial object is required:
//Adafruit_VC0706 cam = Adafruit_VC0706(&Serial1);
void setup() {
// When using hardware SPI, the SS pin MUST be set to an
// output (even if not connected or used). If left as a
// floating input w/SPI on, this can cause lockuppage.
#if !defined(SOFTWARE_SPI)
#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
if(chipSelect != 53) pinMode(53, OUTPUT); // SS on Mega
#else
if(chipSelect != 10) pinMode(10, OUTPUT); // SS on Uno, etc.
#endif
#endif
Serial.begin(9600);
Serial.println("VC0706 Camera snapshot test");
// see if the card is present and can be initialized:
if (!SD.begin(chipSelect)) {
Serial.println("Card failed, or not present");
// don't do anything more:
return;
}
// Try to locate the camera
if (cam.begin()) {
Serial.println("Camera Found:");
} else {
Serial.println("No camera found?");
return;
}
// Print out the camera version information (optional)
char *reply = cam.getVersion();
if (reply == 0) {
Serial.print("Failed to get version");
} else {
Serial.println("-----------------");
Serial.print(reply);
Serial.println("-----------------");
}
// Set the picture size - you can choose one of 640x480, 320x240 or 160x120
// Remember that bigger pictures take longer to transmit!
cam.setImageSize(VC0706_640x480); // biggest
//cam.setImageSize(VC0706_320x240); // medium
//cam.setImageSize(VC0706_160x120); // small
// You can read the size back from the camera (optional, but maybe useful?)
uint8_t imgsize = cam.getImageSize();
Serial.print("Image size: ");
if (imgsize == VC0706_640x480) Serial.println("640x480");
if (imgsize == VC0706_320x240) Serial.println("320x240");
if (imgsize == VC0706_160x120) Serial.println("160x120");
Serial.println("Snap in 3 secs...");
delay(3000);
if (! cam.takePicture())
Serial.println("Failed to snap!");
else
Serial.println("Picture taken!");
// Create an image with the name IMAGExx.JPG
char filename[13];
strcpy(filename, "IMAGE00.JPG");
for (int i = 0; i < 100; i++) {
filename[5] = '0' + i/10;
filename[6] = '0' + i%10;
// create if does not exist, do not open existing, write, sync after write
if (! SD.exists(filename)) {
break;
}
}
// Open the file for writing
File imgFile = SD.open(filename, FILE_WRITE);
// Get the size of the image (frame) taken
uint16_t jpglen = cam.frameLength();
Serial.print("Storing ");
Serial.print(jpglen, DEC);
Serial.print(" byte image.");
int32_t time = millis();
pinMode(8, OUTPUT);
// Read all the data up to # bytes!
byte wCount = 0; // For counting # of writes
while (jpglen > 0) {
// read 32 bytes at a time;
uint8_t *buffer;
uint8_t bytesToRead = min(32, jpglen); // change 32 to 64 for a speedup but may not work with all setups!
buffer = cam.readPicture(bytesToRead);
imgFile.write(buffer, bytesToRead);
if(++wCount >= 64) { // Every 2K, give a little feedback so it doesn't appear locked up
Serial.print('.');
wCount = 0;
}
//Serial.print("Read "); Serial.print(bytesToRead, DEC); Serial.println(" bytes");
jpglen -= bytesToRead;
}
imgFile.close();
time = millis() - time;
Serial.println("done!");
Serial.print(time); Serial.println(" ms elapsed");
}
void loop() {
}