我是学生,我必须根据此文档XAPP213创建一个PicoBlaze 8位微控制器。
当我必须运行跳转或调用指令时,我遇到了问题:
当我跳转或调用下一条指令时,我被迫成为一个NULL指令,因此我的程序计数器(女巫给我新的ADDRESS)保持相同的含义,即他保持2个时钟相同的地址,并且读取两次关于巫婆的指示我跳了或者我打过电话。
如果不发生这种情况我该怎么办?
如果有帮助,这是我的程序计数器代码:
library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.STD_LOGIC_UNSIGNED.all;
use IEEE.NUMERIC_STD.all;
entity DL_PROGRAM_COUNTER is
port(
SELECT_1 : in BIT;
SELECT_0 : in BIT;
CARRY_IN : in BIT;
CLK : in BIT;
RESET : in BIT;
ADR : in BIT_VECTOR(7 downto 0);
IESIRE_STACK : in BIT_VECTOR(7 downto 0);
ADDRESS : out BIT_VECTOR(7 downto 0)
);
end DL_PROGRAM_COUNTER;
--}} End of automatically maintained section
architecture DL_A_PROGRAM_COUNTER of DL_PROGRAM_COUNTER is
component DL_GENERIC_MUX is
generic (Numar_biti_selectie: NATURAL :=1; Numar_biti_cale_date: NATURAL:=1);
port (date: in BIT_VECTOR(0 to (2**Numar_biti_selectie)*Numar_biti_cale_date - 1); -- date <= a0 & a1
sel: in BIT_VECTOR(Numar_biti_selectie-1 downto 0);
Y: out BIT_VECTOR(Numar_biti_cale_date-1 downto 0)
);
end component;
component DL_GENERIC_REGISTRU_PASTRARE is
port(date: in BIT_VECTOR(7 downto 0);
clk,ce,reset: in BIT;
Q: out BIT_VECTOR(7 downto 0)
);
end component;
signal intermediar,iesire_1,iesire_0,aresa_urmatoare: BIT_VECTOR(7 downto 0);
signal date1,date0: BIT_VECTOR(0 to 15);
signal sel1,sel0: BIT_VECTOR(0 downto 0);
begin
COPIERE1: process(intermediar,ADR)
begin
for k in 0 to 7 loop
date1(k) <= intermediar(7-k);
date1(8+k) <= ADR(7-k);
end loop;
end process;
sel1(0) <= SELECT_1;
MUX1: DL_GENERIC_MUX generic map(1,8) port map(date1,sel1,iesire_1);
COPIERE0: process(iesire_1,IESIRE_STACK)
begin
for k in 0 to 7 loop
date0(k) <= iesire_1(7-k);
date0(8+k) <= IESIRE_STACK(7-k);
end loop;
end process;
sel0(0) <= SELECT_0;
MUX2: DL_GENERIC_MUX generic map(1,8) port map(date0,sel0,iesire_0);
ADDER:process(iesire_0,CARRY_IN)
variable rez: INTEGER;
begin
rez := CONV_INTEGER(TO_STDLOGICVECTOR(iesire_0));
if CARRY_IN = '1' then
rez := rez + 1;
end if;
aresa_urmatoare <= TO_BITVECTOR(STD_LOGIC_VECTOR(TO_UNSIGNED(rez, aresa_urmatoare'length)));
end process;
REGISTRU: DL_GENERIC_REGISTRU_PASTRARE port map(aresa_urmatoare,CLK,'1',RESET,intermediar);
ADDRESS <= intermediar;
end DL_A_PROGRAM_COUNTER;
以下是它的外观框图:
跳转:
select_1 <= '1';
select_0 <= '0';
carry_in <= '0';
致电:
select_1 <= '1';
select_0 <= '0';
carry_in <= '0';
表示NULL指令:
select_1 <= '0';
select_0 <= '0';
carry_in <= '0';