如果我外部用64K flash.64k SRAM.和几个外部芯片. 那么我可否这样来连接:
FLASH的连接:
FLASH TMS320VC5402 A0..A15 <==>A0..A15 D0..D15 <==>D0..D15 /OE <==> NOT (RW) OR PS /WE <==>(RW) OR PS /CE <==>MEMSTRB OR PS
SRAM 的连接 A0..A15 <==>A0..A15 D0..D15 <==>D0..D15 /OE <==> NOT (RW) OR DS /WE <==> RW OR DS /CS <==> MEMSTRB OR DS
IO:4个外部IC A3,A2,A1,A0 1, 1, 1, 0 1, 1, 0, 1 1, 0, 1, 1 0, 1, 1, 1
U1WR <==> RW OR IOS; U1RD <==> NOT (RW) OR IOS; CS1=A0(低电平有效) 访问地址:0xXXXe
U2WR <==> RW OR IOS; U2RD <==> NOT (RW) OR IOS; CS2=A1 访问地址:0xXXXd
U3WR <==> RW OR IOS; U3RD <==> NOT (RW) OR IOS; CS3=A2 访问地址:0xXXXB
U4WR <==> RW OR IOS; U4RD <==> NOT (RW) OR IOS; CS4=A3 访问地址:0xXXX7 上面用到了或门
看到很多都用CPLD来做译码..或门速度不够吗? 我这样做可行吗????
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