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[C64] CIA: oneshot mode reg is considered for 2 enable cycles

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This commit is contained in:
Gyorgy Szombathelyi
2018-12-18 19:42:03 +01:00
parent c934e81ac9
commit 99f2fe1b3c
1 changed files with 9 additions and 14 deletions
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23
cores/c64/rtl/cia6526.vhd
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@@ -462,14 +462,10 @@ begin
variable timerAInput : std_logic;
variable timerBInput : std_logic;
variable newTimerB : unsigned(15 downto 0);
variable new_cra_runmode : std_logic;
variable new_crb_runmode : std_logic;
begin
if rising_edge(clk) then
loadTimerA <= '0';
loadTimerB <= '0';
new_cra_runmode := cra_runmode;
new_crb_runmode := crb_runmode;
if resetIrq then
intr_timerA <= '0';
@@ -498,27 +494,28 @@ begin
timerAToggle <= timerAToggle or di(0);
end if;
cra_start <= di(0);
new_cra_runmode := di(3);
cra_runmode_reg <= di(3);
when X"F" =>
if crb_start = '0' then
-- Only set on rising edge
timerBToggle <= timerBToggle or di(0);
end if;
crb_start <= di(0);
new_crb_runmode := di(3);
crb_runmode_reg <= di(3);
when others => null;
end case;
end if;
if reset = '1' then
new_cra_runmode := '0';
new_crb_runmode := '0';
cra_runmode_reg <= '0';
crb_runmode_reg <= '0';
end if;
cra_runmode <= new_cra_runmode;
crb_runmode <= new_crb_runmode;
if enable = '1' then
cra_runmode <= cra_runmode_reg;
crb_runmode <= crb_runmode_reg;
--
-- process timer A
--
@@ -539,9 +536,8 @@ begin
loadTimerA <= '1';
timerAPulse <= '1';
timerAToggle <= not timerAToggle;
if (new_cra_runmode or cra_runmode) = '1' then
if (cra_runmode_reg or cra_runmode) = '1' then
cra_start <= '0';
newTimerA := (others => '0');
end if;
end if;
if forceTimerA = '1' then
@@ -577,9 +573,8 @@ begin
loadTimerB <= '1';
timerBPulse <= '1';
timerBToggle <= not timerBToggle;
if (new_crb_runmode or crb_runmode) = '1' then
if (crb_runmode_reg or crb_runmode) = '1' then
crb_start <= '0';
newTimerB := (others => '0');
end if;
end if;
if forceTimerB = '1' then