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23 lines
651 B
Markdown
23 lines
651 B
Markdown
7 years ago
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Tutorial 05 - UART0, PL011
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==========================
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This tutorial does the same as tutorial 04, but it prints the serial number on UART0. As such, it can be used
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easily with qemu, like
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```sh
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$ qemu-system-aarch64 -M raspi3 -kernel kernel8.img -serial stdio
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My serial number is: 0000000000000000
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```
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Uart.h, uart.c
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--------------
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Before we could use a rate divisor value, we must establish a valid clock rate for the PL011. It's done
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via mailboxes, with the same property channel we used earlier. Otherwise this interface is identical to the
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UART1 one.
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Main
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----
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We query the board's serial number and then we display it on the serial console.
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