38 lines
1.2 KiB
C
38 lines
1.2 KiB
C
/* Second steps into using program memory */
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/* Storing the addresses in pointers */
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#include <avr/io.h>
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#include <util/delay.h>
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#include <avr/pgmspace.h>
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#include "USART.h"
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const char myVeryLongString[] PROGMEM = "\r\nHi there, \
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this is an example of a long string.\r\n\
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The kind that you wouldn't want to store in RAM.\r\n";
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const uint16_t sixteenBits PROGMEM = 12345;
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int main(void) {
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initUSART();
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const char *stringPointer;
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const uint16_t *wordPointer;
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uint8_t i;
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char oneLetter;
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stringPointer = &myVeryLongString[0]; /* address of first char */
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// stringPointer = myVeryLongString; /* same as above */
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wordPointer = &sixteenBits; /* address of first byte */
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while (1) {
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for (i = 0; i < sizeof(myVeryLongString); i++) {
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oneLetter = pgm_read_byte(stringPointer + i);
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transmitByte(oneLetter);
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_delay_ms(100); /* slow it down to simulate typing effect :) */
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}
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_delay_ms(1000);
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printWord(pgm_read_word(wordPointer));
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} /* End event loop */
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return 0; /* This line is never reached */
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}
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