33 lines
583 B
C
33 lines
583 B
C
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#include "sram.h"
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// 23LCV512 64kB SPI SRAM
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uint8_t sram_status() {
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uint8_t v;
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PORTB &= ~(1 << 2);
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spi_transfer(0x05);
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v = spi_transfer(0x00);
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PORTB |= (1 << 2);
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return v;
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}
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uint8_t sram_read(uint16_t addr) {
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uint8_t v;
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PORTB &= ~(1 << 2);
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spi_transfer(0x03);
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spi_transfer(addr & 0xFF);
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spi_transfer(addr > 8);
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v = spi_transfer(0x00);
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PORTB |= (1 << 2);
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return v;
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}
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void sram_write(uint16_t addr, uint8_t v) {
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PORTB &= ~(1 << 2);
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spi_transfer(0x02);
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spi_transfer(addr & 0xFF);
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spi_transfer(addr > 8);
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spi_transfer(v);
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PORTB |= (1 << 2);
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}
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