33 lines
680 B
C
33 lines
680 B
C
#define UART_BASE 0xc010
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#define UART_DATA ((volatile char*) (UART_BASE + 0x00))
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#define UART_STATUS ((volatile char*) (UART_BASE + 0x02))
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#define UART_STATUS_RXNE_pos 1
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#define UART_STATUS_RXNE_msk (1 << UART_STATUS_RXNE_pos)
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#define UART_STATUS_TXE_pos 0
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#define UART_STATUS_TXE_msk (1 << UART_STATUS_TXE_pos)
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const char hello[] = "Hello, world!";
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int uart_tx_available() {
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return (*UART_STATUS & UART_STATUS_TXE_msk) != 0;
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}
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void uart_send(const char* data, int len) {
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for (int i = 0; i < len; ++i) {
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while (!uart_tx_available()) {
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}
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*UART_DATA = data[i];
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}
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}
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int main() {
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uart_send(hello, sizeof(hello));
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while (1) {
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}
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// never returns
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}
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