C8085 Datasheet | Intel

features of 8085 µp are : It is a 8 bit microprocessor. It is manufactured with N-MOS technology. It has 16 bit address bus and hence can address upto 216 = 65536 bytes (64KB) memory locations through A0-A15. The first 8 lines of address bus and 8 lines of data bus are multiplexed AD0 - AD7. - M. Krishna Kumar MM/M1/LU2/V1/2004 8085 Microprocessor ( cont..) - - - - - - - Data bus is a group of 8 lines D0 - D7. It supports external interrupt request. A 16 bit program counter (PC) A 16 bit stack pointer (SP) Six 8-bit general purpose register arranged in pairs: BC, DE, HL. It requires a signal +5V power supply and operates at 6.144 MHZ single phase clock. It is enclosed with 40 pins DIP ( Dual in line package ). M. Krishna Kumar MM/M1/LU2/V1/2004 8085 Microprocessor ( cont..) Memory: - Program, data and stack memories occupy the same memory space. The total addressable memory size is 64 KB. - Program memory - program can be located anywhere in memory. Jump, branch and call instructions use 16-bit addresses, i.e. they can be used to jump/branch anywhere within 64 KB. All jump/branch instructions use absolute addressing. M. Krishna Kumar MM/M1/LU2/V1/2004 8085 Microprocessor ( cont..) - Data memory - the processor always uses 16-bit addresses so that data can be placed anywhere. - Stack memory is limited only by the size of memory. Stack grows downward. - First 64 bytes in a zero memory page should be reserved for vectors used by RST instructions. M. Krishna Kumar MM/M1/LU2/V1/2004 Pin Diagram of 8085 X1 X2 RESET OUT SOD SID TRAP RST 7.5 RST 6.5 RST 5.5 INTR _____ INTA AD0 AD1 AD2 AD3 AD4 AD5 AD6 AD7 VSS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 Vcc HOLD HLDA CLK ( OUT) READY ___ 1 Serial i/p, o/p signals RESET IN __ IO / M S RD ___ 8085...