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September 14, 2024 13:55
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ATMega8_Rescue_ATMega32A
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| #include <avr/io.h> | |
| #include <util/delay.h> | |
| #define HFUSE 0xDF // Default for ATmega48/88/168, for others see | |
| #define LFUSE 0x62 // http://www.engbedded.com/cgi-bin/fc.cgi | |
| /* | |
| #define DATA PORTD // PORTD = Arduino Digital pins 0-7 | |
| #define DATAD DDRD // Data direction register for DATA port | |
| #define VCC 8 PB0 | |
| #define RDY 12 PB4 // RDY/!BSY signal from target | |
| #define OE 11 PB3 | |
| #define WR 10 PB2 | |
| #define BS1 9 PB1 | |
| #define XA0 13 PB5 | |
| #define XA1 18 PC4 // Analog inputs 0-5 can be addressed as | |
| #define PAGEL 19 PC5 // digital outputs 14-19 | |
| #define RST 14 PC0 // Output to level shifter for !RESET | |
| #define BS2 16 PC2 | |
| #define XTAL1 17 PC3 | |
| #define BUTTON 15 PC1 // Run button | |
| #define LED 0 | |
| */ | |
| // PORTB | |
| #define _XA0 (1<<5) // PB5-SCK | |
| #define _RDY (1<<4) // PB4-MISO | |
| #define _OE (1<<3) // PB3-MOSI | |
| #define _WR (1<<2) // PB2-SS | |
| #define _BS1 (1<<1) // PB1-OC1A | |
| #define _VCC (1<<0) // PB0-PCINT0 | |
| // PORTC | |
| #define _XA1 (1<<4) // PC4-SDA | |
| #define _PAGEL (1<<5) // PC5-SCL | |
| #define _RST (1<<0) // PC0-ADC0 | |
| #define _BS2 (1<<2) // PC2-ADC2 | |
| #define _XTAL1 (1<<3) // PC3-ADC3 | |
| #define _BUTTON (1<<1) // PC1-ADC1 | |
| void HardwareInit() | |
| { | |
| // PB4-MISO | |
| DDRB = ~(_RDY); // all outputs except RDY (PB4) | |
| PORTB = 0x00; // no pull-up | |
| // PC1-ADC1 & PC0-ADC0 | |
| DDRC = ~(_BUTTON); // all outputs except BUTTON (PC1) | |
| PORTC = (_BUTTON)|(_RST); // pull-up and 12V off (PC0 = 1) | |
| DDRD = 0xff; // all outputs | |
| PORTD = 0x00; | |
| } | |
| void sendcmd(unsigned char command) | |
| { | |
| // PC4-SDA | |
| PORTC |= _XA1; | |
| // PB5-SCK & PB1-OC1A | |
| PORTB &= ~(_XA0|_BS1); | |
| // PCINT [16..23] | |
| PORTD = command; | |
| // PC3-ADC3 : crystal pulse 1000-Hz | |
| PORTC |= _XTAL1; | |
| _delay_ms(1); | |
| PORTC &= ~(_XTAL1); | |
| _delay_ms(1); | |
| } | |
| void writefuse(unsigned char fuse, char highbyte) | |
| { | |
| // PB5-SCK & PC4-SDA | |
| PORTC &= ~(_XA1); | |
| PORTB |= _XA0; | |
| _delay_ms(1); | |
| // Send fuse via 8-bit PORT-D [0..7] | |
| PORTD = fuse; | |
| // pulse 1000-Hz : | |
| PORTC |= _XTAL1; | |
| _delay_ms(1); | |
| PORTC &= ~(_XTAL1); | |
| // HFUSE | LFUSE -> PB1-OC1A: | |
| if (highbyte) | |
| PORTB |= _BS1; | |
| else | |
| PORTB &= ~(_BS1); | |
| // PB2-SS/OC1B : | |
| PORTB &= ~(_WR); | |
| _delay_ms(1); | |
| // PB2-SS/OC1B : | |
| PORTB |= _WR; | |
| _delay_ms(100); | |
| } | |
| int main() | |
| { | |
| HardwareInit(); | |
| for (;;) | |
| { | |
| while (PINC & _BUTTON) {} // wait for button | |
| // Initialize pins to enter programming mode | |
| PORTC &= ~(_PAGEL|_XA1|_BS2); | |
| PORTB &= ~(_XA0|_BS1); | |
| // Enter programming mode | |
| PORTB |= _VCC|_WR|_OE; | |
| _delay_ms(1); | |
| PORTC &= ~(_RST); | |
| _delay_ms(1); | |
| // Program HFUSE | |
| sendcmd(0b01000000); | |
| writefuse(HFUSE, 1); | |
| // Program LFUSE | |
| sendcmd(0b01000000); | |
| writefuse(LFUSE, 0); | |
| _delay_ms(1000); // allow button to be released | |
| // Exit programming mode | |
| PORTC |= _RST; | |
| // Turn off outputs | |
| PORTD = 0x00; | |
| PORTB &= ~(_VCC|_WR|_OE|_XA0|_BS1); | |
| PORTC &= ~(_PAGEL|_XA1|_BS2); | |
| } | |
| } |
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