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Update T80

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This commit is contained in:
Gyorgy Szombathelyi 2023-04-15 16:43:26 +02:00
parent 63b4982ab9
commit 5e027238cd
3 changed files with 37 additions and 27 deletions
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26
common/CPU/T80/T80.vhd
View File

@ -233,6 +233,8 @@ architecture rtl of T80 is
signal LDHLSP : std_logic;
signal ADDSPdd : std_logic;
signal IORQ_i : std_logic;
signal Write_i : std_logic;
signal NoRead_i : std_logic;
signal Special_LD : std_logic_vector(2 downto 0);
signal ExchangeDH : std_logic;
signal ExchangeRp : std_logic;
@ -262,6 +264,8 @@ architecture rtl of T80 is
signal No_PC : std_logic;
signal DOR : std_logic_vector(127 downto 0);
signal Really_Wait : std_logic;
begin
REG <= IntE_FF2 & IntE_FF1 & IStatus & DOR & std_logic_vector(PC) & std_logic_vector(SP) & std_logic_vector(R) & I & Fp & Ap & F & ACC when Alternate = '0'
@ -338,8 +342,8 @@ begin
SetEI => SetEI,
IMode => IMode,
Halt => Halt,
NoRead => NoRead,
Write => Write,
NoRead => NoRead_i,
Write => Write_i,
R800_mode => R800_mode,
No_PC => No_PC,
XYbit_undoc => XYbit_undoc);
@ -370,6 +374,8 @@ begin
Q => ALU_Q,
F_Out => F_Out);
Really_Wait <= not Wait_n and (Write_i or not NoRead_i);
ClkEn <= CEN and not BusAck;
T_Res <= '1' when TState = unsigned(TStates) else '0';
@ -679,7 +685,7 @@ begin
end if;
end if;
if (TState = 2 and I_BTR = '1' and IR(0) = '1') or (TState = 1 and I_BTR = '1' and IR(0) = '0') then
if (TState = 2 and Really_Wait = '0' and I_BTR = '1' and IR(0) = '1') or (TState = 1 and I_BTR = '1' and IR(0) = '0') then
ioq := ('0' & DI_Reg) + ('0' & std_logic_vector(ID16(7 downto 0)));
F(Flag_N) <= DI_Reg(7);
F(Flag_C) <= ioq(8);
@ -688,7 +694,7 @@ begin
F(Flag_P) <= not (ioq(0) xor ioq(1) xor ioq(2) xor ioq(3) xor ioq(4) xor ioq(5) xor ioq(6) xor ioq(7));
end if;
if TState = 2 and Wait_n = '1' then
if TState = 2 and Really_Wait = '0' then
if ISet = "01" and MCycle = "111" then
IR <= DInst;
end if;
@ -716,7 +722,7 @@ begin
end if;
end if;
if (TState = 2 and Wait_n = '1') or (TState = 4 and MCycle = "001") then
if (TState = 2 and Really_Wait = '0') or (TState = 4 and MCycle = "001") then
if IncDec_16(2 downto 0) = "111" then
if IncDec_16(3) = '1' then
SP <= SP - 1;
@ -1005,7 +1011,7 @@ begin
signed(RegBusA) + 1;
process (Save_ALU_r, Auto_Wait_t1, ALU_OP_r, Read_To_Reg_r, I_MULU, T_Res,
ExchangeDH, ExchangeWH, IncDec_16, MCycle, TState, Wait_n, LDHLSP)
ExchangeDH, ExchangeWH, IncDec_16, MCycle, TState, Really_Wait, LDHLSP)
begin
RegWEH <= '0';
RegWEL <= '0';
@ -1034,7 +1040,7 @@ begin
RegWEL <= '1';
end if;
if IncDec_16(2) = '1' and ((TState = 2 and Wait_n = '1' and MCycle /= "001") or (TState = 3 and MCycle = "001")) then
if IncDec_16(2) = '1' and ((TState = 2 and Really_Wait = '0' and MCycle /= "001") or (TState = 3 and MCycle = "001")) then
case IncDec_16(1 downto 0) is
when "00" | "01" | "10" =>
RegWEH <= '1';
@ -1047,7 +1053,7 @@ begin
TmpAddr2 <= std_logic_vector(unsigned(signed(SP) + signed(Save_Mux)));
process (Save_Mux, RegBusB, RegBusA_r, ID16, I_MULU, MULU_Prod32, MULU_tmp, T_Res,
ExchangeDH, ExchangeWH, IncDec_16, MCycle, TState, Wait_n, LDHLSP, TmpAddr2, WZ)
ExchangeDH, ExchangeWH, IncDec_16, MCycle, TState, Really_Wait, LDHLSP, TmpAddr2, WZ)
begin
RegDIH <= Save_Mux;
RegDIL <= Save_Mux;
@ -1204,6 +1210,8 @@ begin
IntCycle_n <= not IntCycle;
IntE <= IntE_FF1;
IORQ <= IORQ_i;
NoRead <= NoRead_i;
Write <= Write_i;
Stop <= I_DJNZ;
-------------------------------------------------------------------------
--
@ -1275,7 +1283,7 @@ begin
if BusReq_s = '1' and BusAck = '1' then
else
BusAck <= '0';
if TState = 2 and Wait_n = '0' then
if TState = 2 and Really_Wait = '1' then
elsif T_Res = '1' then
if Halt = '1' and ( not(Mode = 3 and INT_n = '0' and IntE_FF1 = '0')) then -- halt bug when Mode = 3 , INT_n = '0' and IME=0
Halt_FF <= '1';

2
common/CPU/T80/T80a.vhd
View File

@ -291,7 +291,7 @@ begin
if TState = "001" then
IORQ_int <= not IntCycle_n;
end if;
if TState = "010" then
if TState = "010" and Wait_s = '1' then
IORQ_int <= '0';
end if;
end if;

36
common/CPU/T80/T80pa.vhd
View File

@ -52,6 +52,8 @@
--
-- v2.3: Output last used Address during non-bus MCycle seems more correct.
--
-- v2.4: Use the fixed WAIT_n in T80.vhd
--
library IEEE;
use IEEE.std_logic_1164.all;
@ -103,6 +105,7 @@ architecture rtl of T80pa is
signal TState : std_logic_vector(2 downto 0);
signal CEN_pol : std_logic;
signal CEN : std_logic;
signal Wait_s : std_logic;
begin
CEN <= CEN_p and not CEN_pol;
@ -121,7 +124,7 @@ begin
Write => Write,
RFSH_n => RFSH_n,
HALT_n => HALT_n,
WAIT_n => '1',
WAIT_n => Wait_s,
INT_n => INT_n,
NMI_n => NMI_n,
RESET_n => RESET_n,
@ -154,25 +157,24 @@ begin
CEN_pol <= '0';
elsif CEN_p = '1' and CEN_pol = '0' then
CEN_pol <= '1';
if MCycle = "001" then
if TState = "010" then
IORQ_n <= '1';
MREQ_n <= '1';
RD_n <= '1';
end if;
else
if TState = "001" and IORQ = '1' then
WR_n <= not Write;
RD_n <= Write;
IORQ_n <= '0';
if WAIT_s = '1' or TState /= "010" then
if MCycle = "001" then
if TState = "010" then
IORQ_n <= '1';
MREQ_n <= '1';
RD_n <= '1';
end if;
else
if TState = "001" and IORQ = '1' then
WR_n <= not Write;
RD_n <= Write;
IORQ_n <= '0';
end if;
end if;
end if;
elsif CEN_n = '1' and CEN_pol = '1' then
if TState = "010" then
CEN_pol <= not WAIT_n;
else
CEN_pol <= '0';
end if;
Wait_s <= Wait_n;
CEN_pol <= '0';
if TState = "011" and BUSAK = '1' then
DI_Reg <= DI;
end if;