mitsubishi - Al Kossow's Bitsavers

MITSUBISHI MICROCOMPUTERSMELPS 8-48 MICROCOMPUTERSFUNCTION OF MELPS 8-48 MICROCOMPUTERSSymbolMeaningSymbolMeaningA8-bit register (accumlator)POProgram counterAo-A3The low-order 4 bits of the register APOO-P07The low-order 8 bits of the program counterA4- A 7Ao-An,An+,The high-order 4 bits of the register AThe bits of the register APOS-PO'OPSWThe high-order 3 bits of the program counterProgram status wordbThe value of the bits 5-7 of the first byte machine codeb7 b6 bSThe bits 5- 7 of the first byte machine codeRrRegister designatorBSBUSRegister bank selectCorresponds to the port 0 (bus I/O port)rrORegister numberThe value of bit o ,of the machine coderzr,rOThe value of bits 0-2 of the machine codeAOAuxiliary carry flag 525 ,50The value of bits 0-2 of the stack pointer0Carry flagSPStack pointerDBBData bus bufferST4-ST7Bits 4-7 of the status registerFoFlINTFISFmm7m6mSm4m3m2mlmOmlO m 9 ma(M (A»(M(Rr»(Mx(Rr»MBFSTSFlag 0TFlag 1ToInterrupt flagT1Input buffer full flagTONTFThe value of the 11 -bit addressTFThe second byte (low-order 8 bits) machine code of the11-bit addressThe bits 5-7 of the first byte (high-order 3 bits) machinecode of at he 11 -bit address':j:j:The content of the memory location addressed by the register A@The content of rhe memory location addressed by the register RrThe content of the external memory location addressffiby the register Rr--Memory bank flag +--+System statusTimer / event counterTest pin 0Test pin 1Timer / event counter overflow interrupt flagTimer flagSymbol to indicate the immediate dataSymbol to indicate the cuntent of the memory locationaddress by the registerShows direction of data flowExchanges the contents of dataIInThe value of the immediate data ( )Contents of register. memory location or flagn 7n 6n Sn 4n 3n 2n 1 n 0\OSFPPpThe immediate data of the second byte machine code 1\Output buffer full flagVVPort number -Port designator0Logical A~DInclusive ORExclusive ORNegationContent of flag is set Qr reset after executionP1POThe bits of the machine code corresponding to the port number• MITSUBISHI.... ELECTRIC4-19