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R65C02: correct cycle counts of JMP (ind) and JMP (ind,x) to 6

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Change-Id: I3f7659b0db8d9c6a62577cb5b17052267a0b4154
This commit is contained in:
David Banks 2021-03-13 14:19:45 +00:00
parent c184b6466a
commit 6b67360bf3
1 changed files with 14 additions and 18 deletions
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30
src/AlanD/R65Cx2.vhd
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@ -41,9 +41,9 @@ end R65C02;
-- Rti (6) => fetch, cycle2, stack1, stack2, stack3, cycleJump
-- Jsr (6) => fetch, cycle2, .. cycle5, cycle6, cycleJump
-- Jmp abs (3) => fetch, cycle2, cycleJump
-- Jmp (ind) (5) => fetch, cycle2, cycle3, cycleRead, cycleJump
-- Jmp (ind,x) (5) => fetch, cycle2, cycle3, cycleRead, cycleJump
-- Brk / irq (6) => fetch, cycle2, stack2, stack3, stack4
-- Jmp (ind) (6) => fetch, cycle2, cycle3, cycleRead, cycleRead2, cycleJump
-- Jmp (ind,x) (6) => fetch, cycle2, cycle3, cycleRead, cycleRead2, cycleJump
-- Brk (7) => fetch, cycle2, stack2, stack3, stack4, cycleRead2, cycleJump
-- -----------------------------------------------------------------------
architecture Behavioral of R65C02 is
@ -1058,9 +1058,7 @@ begin
end if;
when cycleRead =>
if opcInfo(opcJump) = '1' then
nextCpuCycle <= cycleJump;
elsif indexOut(8) = '1' then
if opcInfo(opcJump) = '1' or indexOut(8) = '1' then
nextCpuCycle <= cycleRead2;
elsif opcInfo(opcRmw) = '1' then
nextCpuCycle <= cycleRmw;
@ -1070,7 +1068,9 @@ begin
end if;
when cycleRead2 =>
if opcInfo(opcRmw) = '1' then
if opcInfo(opcJump) = '1' then
nextCpuCycle <= cycleJump;
elsif opcInfo(opcRmw) = '1' then
nextCpuCycle <= cycleRmw;
end if;
@ -1104,7 +1104,7 @@ begin
end if;
when cycleStack4 =>
nextCpuCycle <= cycleRead;
nextCpuCycle <= cycleRead2;
when cycleJump =>
if opcInfo(opcIncrAfter) = '1' then
@ -1460,16 +1460,16 @@ begin
nextAddr <= nextAddrZPIndexed;
when cycleRead =>
nextAddr <= nextAddrPc;
if opcInfo(opcJump) = '1' then
nextAddr <= nextAddrIncr;
elsif indexOut(8) = '1' then
if indexOut(8) = '1' then
nextAddr <= nextAddrIncrH;
elsif opcInfo(opcRmw) = '1' then
elsif opcInfo(opcRmw) = '1' or opcInfo(opcJump) = '1' then
nextAddr <= nextAddrHold;
end if;
when cycleRead2 =>
nextAddr <= nextAddrPc;
if opcInfo(opcRmw) = '1' then
if opcInfo(opcJump) = '1' then
nextAddr <= nextAddrIncr;
elsif opcInfo(opcRmw) = '1' then
nextAddr <= nextAddrHold;
end if;
when cycleRmw =>
@ -1542,11 +1542,7 @@ begin
when nextAddrAbs =>
myAddr <= di & T;
when nextAddrAbsIndexed =>
if theOpcode = x"7C" then
myAddr <= (di & T) + (x"00"& X);
else
myAddr <= di & indexOut(7 downto 0);
end if;
when nextAddrZeroPage =>
myAddr <= "00000000" & di;
when nextAddrZPIndexed =>