diff options
Diffstat (limited to 'basys3/basys3.srcs/ppu_dispctl.vhd')
| -rw-r--r-- | basys3/basys3.srcs/ppu_dispctl.vhd | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/basys3/basys3.srcs/ppu_dispctl.vhd b/basys3/basys3.srcs/ppu_dispctl.vhd index 82d154b..725a6f2 100644 --- a/basys3/basys3.srcs/ppu_dispctl.vhd +++ b/basys3/basys3.srcs/ppu_dispctl.vhd @@ -45,7 +45,7 @@ architecture Behavioral of ppu_dispctl is signal TACTIVE, THACTIVE, TVACTIVE : std_logic := '0'; begin NHCOUNT <= PCOUNT mod PPU_VGA_H_TOTAL; - NVCOUNT <= PCOUNT / PPU_VGA_H_TOTAL mod PPU_VGA_V_TOTAL; + NVCOUNT <= (PCOUNT / PPU_VGA_H_TOTAL) mod PPU_VGA_V_TOTAL; THCOUNT <= (PCOUNT / 4) mod (PPU_VGA_H_TOTAL / 2); TVCOUNT <= (PCOUNT / 4) / (PPU_VGA_H_TOTAL / 2) mod (PPU_VGA_V_TOTAL / 2); @@ -68,15 +68,15 @@ begin N_POS_X <= resize(NHCOUNT - PPU_VGA_H_PORCH_BACK, N_POS_X'length) when NHACTIVE = '1' else (others => '0'); N_POS_Y <= resize(NVCOUNT - PPU_VGA_V_PORCH_BACK, N_POS_Y'length) when NVACTIVE = '1' else (others => '0'); - T_POS_X <= resize(THCOUNT - (PPU_VGA_H_PORCH_BACK / 2), X'length); -- TODO: prevent out of range (add THACTIVE) - T_POS_Y <= resize(TVCOUNT - (PPU_VGA_V_PORCH_BACK / 2), Y'length); + T_POS_X <= resize(THCOUNT - (PPU_VGA_H_PORCH_BACK / 4), T_POS_X'length) when N_POS_Y(0) = '0' else + resize(THCOUNT - ((PPU_VGA_H_PORCH_BACK + PPU_VGA_H_BLANK) / 4), T_POS_X'length); -- divide tiny x equally over two native scanlines + T_POS_Y <= resize(TVCOUNT - (PPU_VGA_V_PORCH_BACK / 2), T_POS_Y'length); DATA_I <= RI & GI & BI; ADDR_I <= std_logic_vector(resize(T_POS_X, ADDR_I'length)) when T_POS_Y(0) = '0' else std_logic_vector(resize(T_POS_X, ADDR_I'length) + PPU_SCREEN_WIDTH); - -- TODO: X isn't calculated right, Y seems okay - X <= std_logic_vector(T_POS_X); - Y <= std_logic_vector(T_POS_Y); + X <= std_logic_vector(T_POS_X) when NACTIVE = '1' else (others => '0'); + Y <= std_logic_vector(T_POS_Y) when NACTIVE = '1' else (others => '0'); U_POS_X <= resize(N_POS_X / 2, U_POS_X'length); U_POS_Y <= resize(N_POS_Y / 2, U_POS_Y'length); @@ -108,15 +108,14 @@ begin end process; process(CLK25(1), RESET) - variable V_PCOUNT : unsigned(PPU_VGA_SIGNAL_PIXEL_WIDTH-1 downto 0) := (others => '0'); begin - PCOUNT <= V_PCOUNT; if RESET = '1' then - V_PCOUNT := (others => '0'); + PCOUNT <= (others => '0'); elsif rising_edge(CLK25(1)) then - V_PCOUNT := V_PCOUNT + 1; - if V_PCOUNT = PPU_VGA_SIGNAL_PIXEL_IDX_MAX then - V_PCOUNT := (others => '0'); + if PCOUNT + 1 >= PPU_VGA_SIGNAL_PIXEL_IDX_MAX then + PCOUNT <= (others => '0'); + else + PCOUNT <= PCOUNT + 1; end if; end if; end process; |