diff options
| author | Josh Rahm <joshuarahm@gmail.com> | 2020-12-03 22:45:47 -0700 |
|---|---|---|
| committer | Josh Rahm <joshuarahm@gmail.com> | 2020-12-03 22:45:47 -0700 |
| commit | 9e349913f728e47e09852a20a7e16c405d30cd7b (patch) | |
| tree | f8204d07b4712e9e876fffc2284658e132e8ac8e /src/kern/main.c | |
| parent | 4466725d3facb939f60f598caa684766b50a4235 (diff) | |
| download | stm32l4-9e349913f728e47e09852a20a7e16c405d30cd7b.tar.gz stm32l4-9e349913f728e47e09852a20a7e16c405d30cd7b.tar.bz2 stm32l4-9e349913f728e47e09852a20a7e16c405d30cd7b.zip | |
Double the SPI bandwith by writing only 8 bits to the spi data register instead of 16 (with 8 leading 0's).
Diffstat (limited to 'src/kern/main.c')
| -rw-r--r-- | src/kern/main.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/src/kern/main.c b/src/kern/main.c index 9d93247..c76d025 100644 --- a/src/kern/main.c +++ b/src/kern/main.c @@ -98,7 +98,7 @@ static void spi_write(uint8_t byte) { while (!regget(SPI1.s_r, spi_txe)) ; - SPI1.d_r = byte; + SPI1.dl_r = byte; asm volatile("nop"); } @@ -106,8 +106,6 @@ static void write_rgb(uint8_t red, uint8_t green, uint8_t blue) { #undef BIT #define BIT(b, n) (!!((b) & (1 << (n)))) - spi_write(0); - spi_write( (1 << 7) | (BIT(green, 7) << 6) | (0 << 5) | (0 << 4) | (1 << 3) | (BIT(green, 6) << 2) | (0 << 1) | (0 << 0)); @@ -146,8 +144,6 @@ static void write_rgb(uint8_t red, uint8_t green, uint8_t blue) spi_write( (1 << 7) | (BIT(blue, 1) << 6) | (0 << 5) | (0 << 4) | (1 << 3) | (BIT(blue, 0) << 2) | (0 << 1) | (0 << 0)); - - spi_write(0); } void latch() |