fifi@cosmo.UUCP (A.F.Zinser) (04/08/89)
In article <> beyer@frith.UUCP (Don W Beyer) writes: > I agree, I won't believe it untill _I_ see it either! The Z280 supports following types of multiplication/division: - MULT A,r - MULTU A,r - MULTW HL,rr - MULTUW HL,rr - DIV HL,r - DIVU HL,r - DIVW DEHL,rr - DIVUW DEHL,rr (DEHL => DE & HL taken as 32-bit-register) where rr is one of - BC, DE, HL, IX, IY, SP, nn, (nn), (IX+nn), (IY+nn), (PC+nn) (nn as a 2-byte-adress/offset) and r is one of - A, B, C, D, E, H, L, HX, LX, HY, LY, (HL), (nn), n, (HL+IX|IY), (IX+IY), (IX|IY+n), (IX|IY|HL|PC|SP+nn) (n as 1-byte-offset) These new adressing-modes are supported in most commands (ADC, ADD, AND (all type A,r), ADDW HL,rr, CP A,r, CPW HL,rr, DEC r|rr, DECW rr, EX A,r, IN r,(C), INC{W} (see above), LD r|rr,r|rr (including LD (nn),n, but not LD (nn),(nn)), LDW rr,rr (inc. LDW (nn),nn), OR A,r, OUT (C),r, PUSH/POP rr (inc. PUSH/POP (nn) and PUSH/POP nn), rotation- command in Z80-manner only, SBC/SUB A,r, SBC/SUBW HL,rr, XOR A,r) and few new commands are implemented: - DIV/MULT - EPUM/EPUF/EPUI (for multi-processor-systems) - MEPU (also mp-mode) - PCACHE (cache clear) - TSET r (test register contents and set flags) - TSTI (C) (test input) - LDCTL (for internal organisation/programming) Important are the extended adressing-modes of CALL & JP: - CALL cc,rr - JP cc,rr with cc as well-known from Z80 and rr on of following: - (HL), (PC+nn), nn (CALL & JP) - (IX), (IY) (JP only - like Z80) Some other facts of Z280 - seperate memory- and i/o-wait-states, can be modified by software - cache configurable as data- or instruction-cache (or both) - 16-bit-i/o-adress supported - single-step-mode - user/system - mode (system-SP, user-SP) But... the instruction-set may be a superset to that of the Z80, one opcode differs from Z80 : TSET has the same opcode as SLIA from Z80 (undocumented, but working). using this command, your software is able to distinguish between Z280 and Z80. axel f. zinser [source: Zilog Z280 MPU - Technical Manual, March 1987] (*) Z80, Z280 are registered trademarks of Zilog, Inc. +-------------------------------------------------------------------------+ | _ _ ! ! Axel F. Zinser (_!_) (_!_) ...uunet!mcvax!unido!cosmo!fifi | | Hannover, BRD ! ! fifi@cosmo.UUCP ! ! ! +-------------------------------------------------------------------------+