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#include <rcc/rcc.h>
#include <gpio/pin.h>
#include <spi/spi.h>
#include <os/time.h>
Pin& noe = PA3;
Pin& vsync = PA4;
Pin& clk = PA5; // SCK
Pin& hsync = PA6;
Pin& data = PA7; // MOSI
inline void nopdelay(uint32_t iterations) {
while(iterations--) {
asm volatile("nop");
}
}
uint32_t buf[] = {
0b1001010100000000,
0b1001010100000000,
0b1111010100000000,
0b1001010000000000,
0b1001010100000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
0b0000000000000000,
};
int main() {
// Initialize system timer.
STK.LOAD = 168000000 / 8 / 1000; // 1000 Hz.
STK.CTRL = 0x03;
RCC.enable(RCC.GPIOA);
RCC.enable(RCC.SPI1);
noe.set_mode(Pin::Output);
noe.off();
hsync.set_mode(Pin::Output);
hsync.off();
vsync.set_mode(Pin::Output);
vsync.on();
clk.set_mode(Pin::AF);
clk.set_af(5);
data.set_mode(Pin::AF);
data.set_af(5);
SPI1.reg.CR1 = 0xbfc;
uint32_t row = 0;
while(1) {
// Shift out a row.
SPI1.reg.DR = buf[row];
while(!(SPI1.reg.SR & 0x01));
(void)SPI1.reg.DR;
// Assert vsync if this is first row.
if(row == 0) {
vsync.off();
}
// Strobe hsync.
hsync.on();
nopdelay(10);
hsync.off();
// Deassert vsync.
if(row == 0) {
vsync.on();
}
Time::sleep(1);
row = (row + 1) & 0xf;
}
}
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