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/*Copyright (C) 2004 John OrlandoAVRcam: a small real-time image processing engine.This program is free software; you can redistribute it and/ormodify it under the terms of the GNU General PublicLicense as published by the Free Software Foundation; eitherversion 2 of the License, or (at your option) any later version.This program is distributed in the hope that it will be useful,but WITHOUT ANY WARRANTY; without even the implied warranty ofMERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNUGeneral Public License for more details.You should have received a copy of the GNU General PublicLicense along with this program; if not, write to the Free SoftwareFoundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USAFor more information on the AVRcam, please contact:john@jrobot.netor go to www.jrobot.net for more details regarding the system.*//***********************************************************Module Name: CamInterface.cModule Date: 04/12/2004Module Auth: John OrlandoDescription: This file is responsible for providing aninterface to the OV6620 camera hardware. This includesan interface to CamInterface.S for certain low-level,optimized camera access routines.Revision History:Date Rel Ver. Notes4/10/2004 0.1 Module created6/30/2004 1.0 Initial release for Circuit Cellarcontest.11/15/2004 1.2 ifdef'd out the resetCam routine, sinceresetting the cam now causes the OV6620'sclock to not be output (we have to startit up after each reset with the externaltiny12 processor).1/16/2005 1.4 Ensure that the TCCR1B register is set sonothing is clocking timer1 at startup.***********************************************************//* Includes */#include <avr/interrupt.h>#include <avr/signal.h>#include <avr/sleep.h>#include <avr/eeprom.h>#include <stdlib.h>#include <string.h>#include "CommonDefs.h"#include "CamInterface.h"#include "Utility.h"#include "UIMgr.h"#include "Executive.h"#include "UartInterface.h"/* Local Variables *//* Local Structures and Typedefs *//* Definitions *///#define OUTPUT_INITIAL_COLOR_MAP 1#define FAST_ACQUIRE 1#define CAM_G_BUS PINB#define CAM_G_BUS_DIR DDRB#define CAM_RB_BUS PINC#define CAM_RB_BUS_DIR DDRC#define CAM_CONTROL_PORT PORTD#define CAM_CONTROL_PORT_DIR DDRD#define CAM_RESET_LINE BIT7#define CAM_PIXEL_CLK_COUNT BIT5#define CAM_HREF BIT4#define CAM_PIXEL_CLK_INT BIT3#define CAM_VSYNC BIT2/* Global Variables *//* NOTE: This file MUST appear first in the Makefile for these variables tobe placed properly in RAM *//* The colorMap[] table provides the membership lookup table to convertRGB or YUV pixel values into actual colors. The membership table contains16 elements for each color channel, concatenated together. The Red (or Y)value is located in the first 16 bytes, the G (or U) value is located inthe second 16 bytes, and the B (or V) value is located in the last 16 bytes:----------------------------------------------------------------------------------|red0|red1|red2|...|red15|green0|green1|green2|...|green15|blue0|blue1|...|blue15|mem:|0x00 0x01 0x02 0x15 0x16 0x17 0x18 0x31 0x32 0x33 0x47 |---------------------------------------------------------------------------------Thus, the red lookup is accessed at colorMap+0, the green lookup is accessedat colorMap+16, and the blue lookup is accessed at colorMap+32. */unsigned char colorMap[NUM_ELEMENTS_IN_COLOR_MAP] __attribute__ ((section (".noinit")));/* Extern Variables *//* These two buffers hold the current and previous linesof pixel data. They are sized to the worst case scenario,where the color changes between every pixel (unrealistic).The format of each buffer is for all the even bytes to holdthe run-length, and the odd bytes to hold the color data. *//* In addition, if we are in frameDump mode, we use these buffersto store the acquired line data...we are actually grabbing ALL of thepixels in a line (176) instead of the 88 we get normally during tracking.But since we have enough to hold 88-RLE blocks, we already have the 176allocated for this... */unsigned char currentLineBuffer[LENGTH_OF_LINE_BUFFER];unsigned char previousLineBuffer[LENGTH_OF_LINE_BUFFER];/* Extern Functions *//* These functions are located in assembly files, and thusmust be externed here so they can be referenced in the source below. */extern void CamIntAsm_waitForNewTrackingFrame(unsigned char *pBuffer, unsigned char *pMemLookup);extern void CamIntAsm_waitForNewDumpFrame(unsigned char *pCurrBuffer, unsigned char *pPrevBuffer);extern void CamIntAsm_acquireTrackingLine(unsigned char *pBuffer, unsigned char *pMemLookup);extern void CamIntAsm_acquireDumpLine(unsigned char *pCurrBuffer, unsigned char *pPrevBuffer);/***********************************************************Function Name: CamInt_initFunction Description: This function is responsiblefor initializing the camera interface. This includessetting up the i/o ports that are used to read thecamera busses, as well as resetting the camera.Inputs: noneOutputs: none***********************************************************/void CamInt_init(void){#if OUTPUT_INITIAL_COLOR_MAPunsigned char asciiBuffer[5];unsigned char i;#endif/* set up the mega8 ports that will be interfacingwith the camera */CAM_CONTROL_PORT_DIR |= (1<<CAM_RESET_LINE); /* cam reset is output */CAM_CONTROL_PORT_DIR |= 0x80; /* set just the MSB as an output */CAM_CONTROL_PORT_DIR &= 0xFB; /* make sure bit2 is clear (input) */CAM_CONTROL_PORT &= 0x7F; /* set reset line low */CAM_G_BUS_DIR &= 0xF0; /* 4-bit G bus all inputs */CAM_G_BUS_DIR |= 0xF0; /* disable the pull-up on PB4 and PB5 */CAM_RB_BUS_DIR &= 0xF0; /* 4-bit RB bus all inputs *//* ensure that timer1 is disabled to start...eventually, when PCLK needsto feed timer1 through the external counter, it will be enabled on an"as needed" basis...*/TCCR1B &= ~( (1<<CS12)|(1<<CS11)|(1<<CS10) );/* we'll turn on the interrupt after we assign the initial TCNT value *//* set up External Interrupt1 to interrupt us on rising edges (HREF)...this is needed to indicate when the first pixel of each line is about to start, sowe can synch up with it...this interrupt will be disabled once HREF goes high */MCUCR |= (1<<ISC11) | (1<<ISC10); /* rising edge interrupt *//* the interrupt will be enabled when we are ready to detect the rising edge ofHREF...its now primed and ready to go *//* set up External Interrupt0 to interrupt us on rising edges (VSYNC) */MCUCR |= (1<<ISC01) | (1<<ISC00); /* rising edge interrupt */GICR |= (1<<INT0); /* interrupt request enabled *//* set up TimerO to count and be clocked from an external pulse source(HREF) on falling edges...eventually, we need to enable the interruptfor this! FIX THIS */TCCR0 = (1<<CS02)|(1<<CS01)|(0<<CS00);/* setting up the PCLK counter with Timer1 will be done right afterwe start receiving pixels in each line...we sacrifice the first pixelin each line, but we'll account for it...*//* set up the mega8 so that its sleep mode puts it in an IDLE sleepmode, where it can wake up as fast as possible */set_sleep_mode(SLEEP_MODE_IDLE);/* umm....we need to actually enable the sleep mode...*/MCUCR |= 0x80;/* initialize the memLookup table */memset(colorMap,0x00,NUM_ELEMENTS_IN_COLOR_MAP);/* read the color map out of EEPROM */eeprom_read_block(colorMap, (unsigned char*)0x01,NUM_ELEMENTS_IN_COLOR_MAP);#if OUTPUT_INITIAL_COLOR_MAPUIMgr_txBuffer("\r\n",2);for (i=0; i<NUM_ELEMENTS_IN_COLOR_MAP; i++){memset(asciiBuffer,0x00,5);itoa(colorMap[i],asciiBuffer,10);UIMgr_txBuffer(asciiBuffer,3);UIMgr_txBuffer(" ",1);if (i==15 || i == 31){/* break up the output */UIMgr_txBuffer("\r\n",2);}}#endif#ifndef NO_CRYSTALCamInt_resetCam();#endif}/***********************************************************Function Name: CamInt_resetCamFunction Description: This function is responsiblefor resetting the camera. This is accomplished bytoggling the reset line on the OV6620 for ~100 mS.Inputs: noneOutputs: noneIMPORTANT NOTE: This function has effectively been removedsince resetting the camera now causes the camera to notoutput the clock signal. Thus, if we reset the cam, theAVR has no clock, and thus doesn't run...***********************************************************/void CamInt_resetCam(void){#if 0CAM_CONTROL_PORT |= (1<<CAM_RESET_LINE); /* cam reset line high */Utility_delay(500);CAM_CONTROL_PORT &= (0<<CAM_RESET_LINE); /* cam reset line low */Utility_delay(100);#endif}