diff options
| author | Keith Packard <keithp@keithp.com> | 2017-11-02 09:10:54 -0700 |
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2017-11-02 09:10:54 -0700 |
| commit | 2418a1297af8f43e338067321779328c59b4a96c (patch) | |
| tree | 76ecbecde63c62992f5cf4baa1b46bd966017110 | |
| parent | 83929cd290279963b01b2ccd52c70d61bdeff6b0 (diff) | |
altos: Add vblank signal to vga driver
Allow applications to sync with vblank.
Signed-off-by: Keith Packard <keithp@keithp.com>
| -rw-r--r-- | src/drivers/ao_vga.c | 6 | ||||
| -rw-r--r-- | src/drivers/ao_vga.h | 2 |
2 files changed, 8 insertions, 0 deletions
diff --git a/src/drivers/ao_vga.c b/src/drivers/ao_vga.c index 909e3109..59658caf 100644 --- a/src/drivers/ao_vga.c +++ b/src/drivers/ao_vga.c @@ -91,6 +91,8 @@ static uint32_t *scanline; (en << STM_DMA_CCR_EN)) +uint8_t ao_vga_vblank; + void stm_tim2_isr(void) { int16_t line = stm_tim3.cnt; @@ -111,6 +113,10 @@ void stm_tim2_isr(void) if (((line - VBLANK_END) & 1)) scanline += AO_VGA_STRIDE; } else { + if (line == VBLANK_START) { + ao_vga_vblank = 1; + ao_wakeup(&ao_vga_vblank); + } scanline = ao_vga_fb; } stm_tim2.sr = 0; diff --git a/src/drivers/ao_vga.h b/src/drivers/ao_vga.h index 7d9d6b39..92cdb76c 100644 --- a/src/drivers/ao_vga.h +++ b/src/drivers/ao_vga.h @@ -36,4 +36,6 @@ extern uint32_t ao_vga_fb[AO_VGA_STRIDE * AO_VGA_HEIGHT]; extern const struct ao_bitmap ao_vga_bitmap; +extern uint8_t ao_vga_vblank; + #endif /* _AO_VGA_H_ */ |