Martin Smith
A Simple library to capture pictures from the uCam by 4D Systems
Diff: uCam.cpp
- Revision:
- 0:68395cd065e4
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/uCam.cpp Tue May 29 08:01:20 2012 +0000
@@ -0,0 +1,391 @@
+#include "uCam.h"
+#include "mbed.h"
+
+#define DEBUG
+
+// Set up some memory to hold the commands
+const unsigned char SYNC[] = {0xAA, 0x0D, 0x00, 0x00, 0x00, 0x00};
+const unsigned char ACK[] = {0xAA, 0x0E, 0x0D, 0x00, 0x00, 0x00};
+const unsigned char BAUD_115200[] = {0xAA, 0x07, 0x01, 0x0F, 0x00, 0x00};
+const unsigned char BAUD_737280[] = {0xAA, 0x07, 0x00, 0x04, 0x00, 0x00};
+const unsigned char BAUD_921600[] = {0xAA, 0x07, 0x01, 0x01, 0x00, 0x00};
+const unsigned char BAUD_1228800[] = {0xAA, 0x07, 0x02, 0x00, 0x00, 0x00};
+const unsigned char GET_PICTURE[] = {0xAA, 0x04, 0x02, 0x00, 0x00, 0x00}; // take snapshot picture
+
+int picture_size; // To track the current picture size
+DigitalOut led1(LED1),led2(LED2),led3(LED3),led4(LED4);
+
+uCam::uCam(PinName tx, PinName rx, int buffer)
+ : _uCam(tx,rx,buffer) {
+
+ // Set the initial baud rate
+ _uCam.baud(115200);
+}
+
+// Waits for an response from the uCam module and checks that a valid ACK was received
+int uCam::Get_Response(unsigned char type, unsigned char command) {
+ // First wait for the uCam module to send the reply or timeout
+ // This waits for the module to become readable or timesout after 50 ms
+ char times = 0; // Variable to check for timeouts
+ do {
+ wait(0.001); // Wait 1 ms
+ times++; // Inc variable
+ if (_uCam.readable())
+ break;
+ } while (times < 100 );
+ // Check if it timed out
+ if (times > 99) {
+ printf("\n\r Response Timeout");
+ return(0);
+ }
+ // Get the reply from the uCam module (will be 6 bytes
+ unsigned char reply[6] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
+ for (int i=0; i<6; i++) {
+ reply[i] = _uCam.getc();
+ }
+ // Check reply was valid, A valid ACK should be 0xAA, 0x0E, Command ID, X, 0x00, 0x00
+ if (reply[0] == 0xAA && reply[1] == type && reply[2] == command && reply[4] == 0x00 && reply[5] == 0x00)
+ // It was an ACK so return true
+ return(1);
+ else {
+ // Reply was invalid so print the reply and return false
+ return(0);
+ }
+}
+
+int uCam::Sync() {
+ // This will give 60 attempts to sync with the uCam module
+ for (int i=0; i<=10; i ++) {
+ // Send out the sync command
+ for (int i=0; i<6; i++) {
+ _uCam.putc(SYNC[i]);
+ }
+ // Check if the response was an ACK
+ if (Get_Response(_ACK,SYNC[1])) {
+ // It was an ACK so now get the next response - it should be a sync
+ if (Get_Response(_SYNC,0x00)) {
+ // We need a small delay (1ms) from receiving the SYNC response and sending an ACK in return
+ wait(0.001);
+ for (int i=0; i<6; i++) {
+ _uCam.putc(ACK[i]);
+ }
+ // Everything is now complete so return true
+ return(1);
+ }
+ }
+ // Wait a while and try again
+ wait(0.01);
+ printf("\n\r Sync failed - trying again");
+ }
+ // Something went wrong so return false
+ return(0);
+}
+
+int uCam::SetBaud(int baud) {
+ // Send out the set baud command
+ for (int i=0; i<6; i++) {
+ // Select the correct data for the desired baud
+ if (baud == 115200)
+ _uCam.putc(BAUD_115200[i]);
+ else if (baud == 737280)
+ _uCam.putc(BAUD_737280[i]);
+ else if (baud == 921600)
+ _uCam.putc(BAUD_921600[i]);
+ else if (baud == 1228800)
+ _uCam.putc(BAUD_1228800[i]);
+ }
+
+ // Check if the response was an ACK
+ if (Get_Response(_ACK,0x07)) {
+ // An ACk was received so we can now set the mbed to the new baud rate
+ _uCam.baud(baud);
+ // New baud rate confirmed - return true
+ return(1);
+ } else
+ // Something went wrong - return false
+ return(0);
+}
+
+int uCam::Initial(unsigned char COLOUR, unsigned char RES) {
+ // Set up a buffer to hold the uCam response
+ unsigned char buf[6] = {0xAA, 0x01, 0x00, COLOUR, 0x00, 0x00};
+
+ //Amend the initial command for the type of image
+ if (buf[3]==0x07) {
+ buf[5] = RES; // The image is a JPEG so set byte 5
+ } else {
+ buf[4] = RES; // The image is RAW so set byte 4
+ }
+
+ // Get the number of bytes to be transferred
+ // Start by finding out how many bytes per pixel
+ if (COLOUR == GREY_8BIT || COLOUR == COLOUR_8BIT) {
+ picture_size = 1;
+ } else if (COLOUR == COLOUR_16BIT) {
+ picture_size = 2;
+ }
+ // Then multiply this by the number of pixels
+ if (RES == RAW_80x60)
+ picture_size = picture_size*80*60;
+ else if (RES == RAW_160x120)
+ picture_size = picture_size*160*120;
+ else if (RES == RAW_320x240)
+ picture_size = picture_size*320*240;
+ else if (RES == RAW_640x480)
+ picture_size = picture_size*640*480;
+ else if (RES == RAW_128x128)
+ picture_size = picture_size*128*128;
+ else if (RES == RAW_128x96)
+ picture_size = picture_size*128*96;
+
+ // Send out the initial command
+ for (int i=0; i<6; i++) {
+ _uCam.putc(buf[i]);
+ }
+
+ // Check for ACK
+ if (Get_Response(_ACK,0x01)) {
+ // An ACk was received - return true
+ return(1);
+ } else {
+ // Something went wrong - return false
+ return(0);
+ }
+}
+
+int uCam::Get_Picture(unsigned char *data) {
+
+ // Send out the get picture command
+ for (int i=0; i<6; i++) {
+ _uCam.putc(GET_PICTURE[i]);
+ }
+
+ if (!Get_Response(_ACK,0x04))
+ // Something went wrong
+ return(0);
+
+ // Get response from uCam
+ for (int i=0; i<picture_size; i++) {
+ if (_uCam.readable())
+ data[i] = _uCam.getc();
+ else {
+ i--;
+ }
+ }
+
+ // We need a small delay (1ms) from receiving the SYNC response and sending an ACK in return
+ wait(0.001);
+ for (int i=0; i<6; i++) {
+ _uCam.putc(ACK[i]);
+ }
+ // Everything is now complete so return true
+ return(1);
+}
+
+int uCam::Save_Picture_To_Memory(FeRAM &flash, int address) {
+ // Variables
+ unsigned char buf[6]; // Buffer to save data from uCam before its written to flash
+ int length; // The length of the incoing data (sent in data packet from uCam)
+ char binned = 0; // Escape variable to break out of function if some data isn't sent from uCam
+ Timer bin; // Timer to see if uCam has hung
+
+ Timer t;
+ t.start();
+
+ // Send out the get picture command
+ for (int i=0; i<6; i++) {
+ _uCam.putc(GET_PICTURE[i]);
+ }
+
+ if (!Get_Response(_ACK,0x04))
+ // Something went wrong
+ return(0);
+#ifdef DEBUG
+ printf("\n Getting picture");
+#endif
+ // Get the first 6 bytes
+ // Format 0xAA 0x0A (Data command), Data type, 3 bytes to show length
+ for (int i=0; i<6; i++) {
+ while (!_uCam.readable()) {
+ wait_us(1);
+ }
+ buf[i] = _uCam.getc(); // Get a byte of data
+ }
+ length = (buf[5] << 16) + (buf[4] << 8) + buf[3];
+
+ // Get response from uCam and save to flash
+ bin.start();
+ for (int i=0; i<length; i++) {
+#ifdef DEBUG
+ // See where we are...
+ if (i>length/4)
+ led1 = 1;
+ if (i>length/2)
+ led2 = 1;
+ if (i>length*3/4)
+ led3 = 1;
+#endif
+ // reset the timer
+ bin.reset();
+
+ while (!_uCam.readable()) {
+#ifdef DEBUG
+ led4 = 1; // Turn LED on to show we're waiting
+#endif
+ // Check to see if we have been waiting for more than 10 ms
+ if (bin.read() > 0.01) {
+ printf("\n binned at %d",i);
+ binned = 1;
+ break;
+ }
+ }
+#ifdef DEBUG
+ led4 = 0; // Turn LED off again
+#endif
+
+ // If this if statement runs than it means the uCam module has hung
+ if (binned) {
+ for (; i<length; i++) {
+ flash.write_byte(i + address, 0x00); // Fill the remaining bytes with 0x00
+ }
+ break; // This breaks out of the loop and writes an ACk back to uCam
+ }
+
+ // uCam has a byte of data ready to read - so go get it!
+ flash.write_byte(i + address, _uCam.getc());
+
+ }
+ // All data has been received so send an ACK back to the uCam module
+ _uCam.putc(0xAA);
+ _uCam.putc(0x0E);
+ _uCam.putc(0x0A);
+ _uCam.putc(0x00);
+ _uCam.putc(0x01);
+ _uCam.putc(0x00);
+
+#ifdef DEBUG
+ t.stop();
+ //printf("\n Finished in %.3f Secs",t.read());
+
+ // Turn all the LEDs off
+ led1 = led2 = led3 = led4 = 0;
+#endif
+
+ // Everything is now complete so return true
+ return(1);
+}
+
+int uCam::Save_Zoom_Picture_To_Memory(FeRAM &flash, int address){
+ // Variables
+ unsigned char buf[6]; // Buffer to save data from uCam before its written to flash
+ unsigned char dummy; // Byte to read in unwanted info
+ int length; // The length of the incoing data (sent in data packet from uCam)
+ int pos = 0;
+ char binned = 0; // Escape variable to break out of function if some data isn't sent from uCam
+ Timer bin; // Timer to see if uCam has hung
+
+ Timer t;
+ t.start();
+
+ // Send out the get picture command
+#ifdef DEBUG
+ printf("\n\n\n\n\n\n\n\n\n\n");
+#endif
+ for (int i=0; i<6; i++) {
+ _uCam.putc(GET_PICTURE[i]);
+ #ifdef DEBUG
+ printf("[%X],",GET_PICTURE[i]);
+ #endif
+ }
+
+ if (!Get_Response(_ACK,0x04))
+ // Something went wrong
+ return(0);
+#ifdef DEBUG
+ printf("\n Getting picture \n");
+#endif
+ // Get the first 6 bytes
+ // Format 0xAA 0x0A (Data command), Data type, 3 bytes to show length
+ for (int i=0; i<6; i++) {
+ while (!_uCam.readable()) {
+ wait_us(1);
+ }
+ buf[i] = _uCam.getc(); // Get a byte of data
+ printf("[%2X],",buf[i]);
+ }
+ length = (buf[5] << 16) + (buf[4] << 8) + buf[3];
+#ifdef DEBUG
+ printf("\n Length is: %d \n[%d] [%d] [%d]",length, buf[5], buf[4], buf[3]);
+#endif
+
+ // Get response from uCam and save to flash
+ bin.start();
+ for (int i=0; i<length; i++) {
+#ifdef DEBUG
+ // See where we are...
+ if (i>length/4)
+ led1 = 1;
+ if (i>length/2)
+ led2 = 1;
+ if (i>length*3/4)
+ led3 = 1;
+#endif
+ // reset the timer
+ bin.reset();
+
+ while (!_uCam.readable()) {
+#ifdef DEBUG
+ led4 = 1; // Turn LED on to show we're waiting
+#endif
+ // Check to see if we have been waiting for more than 10 ms
+ if (bin.read() > 0.01) {
+ printf("\n binned at %d",i);
+ binned = 1;
+ break;
+ }
+ }
+#ifdef DEBUG
+ led4 = 0; // Turn LED off again
+#endif
+
+ // If this if statement runs than it means the uCam module has hung
+ if (binned) {
+ for (; i<length; i++) {
+ flash.write_byte(i + address, 0x00); // Fill the remaining bytes with 0x00
+ }
+ break; // This breaks out of the loop and writes an ACk back to uCam
+ }
+
+ // uCam has a byte of data ready to read - so go get it!
+ // Need to check here if I actually want it!
+ if (i < 320 * 60 * 2 || i > 320 * 180 * 2) // Pixel is too high or low
+ dummy = _uCam.getc();
+ else if (i % 640 < 160) // Pixel is too left
+ dummy = _uCam.getc();
+ else if (i % 640 < 160 + 320){ // Pixel is in the centre - go get it!
+ flash.write_byte(pos + address, _uCam.getc());
+ pos++;
+ } else // Pixel is too right
+ dummy = _uCam.getc();
+
+
+ }
+ // All data has been received so send an ACK back to the uCam module
+ _uCam.putc(0xAA);
+ _uCam.putc(0x0E);
+ _uCam.putc(0x0A);
+ _uCam.putc(0x00);
+ _uCam.putc(0x01);
+ _uCam.putc(0x00);
+
+#ifdef DEBUG
+ t.stop();
+ //printf("\n Finished in %.3f Secs",t.read());
+
+ // Turn all the LEDs off
+ led1 = led2 = led3 = led4 = 0;
+#endif
+
+ // Everything is now complete so return true
+ return(1);
+}
\ No newline at end of file