Model:-55AGeneral:Name:noneCode-Name:Merlin (duplicates -75D name)Family:ClassicLogic:RPNFeatures:scientific, programmableFirsts:timerIntroduction:Date:1975-1-1Price:$395Discontinuation:Date:1977-01-03Price:$335 (price change 1975-10-01)Production-Run:?Display:Type:LED, 7 segmentSize:1 line x 15 charsNumber-Formats:sign, 10 mantissa, ., exp sign, 2 expAnnunciators:...............battery low(true decimal has digit to itself)Data:User-Visible:Smallest:1E-99Largest:9.999999999E99Signif.-Digits:10Internal:Smallest:1E-99Largest:9.999999999E99Signif.-Digits:10Data-Types-and-Sizes:real, 7 bytesMemory:Named-Registers:X, Y, Z, T, Last x, 0-9, .0-.9Flags:noneRegister-Usage:R.0\GSnR.1\GSxR.2\GSx^2R.3\GSyR.4\GSy^2R.5\GSxyNumbered-Registers:20Program-Steps:50Program-Editing:replaceProgram-Display:keycodeUser-RAM-Bytes:224Total-RAM-Bytes:?ROM-Bytes:?Machine-State:prefix key statestack lift enabledisplay modedegrees / radians / gradsregistersprogram countermemoryFile-Types:nonePhysical:Technology-Used:?Processor:?Chip-Count:?Power-Source:3 nickel-cadmium AA cells, ACContinuous-Memory:noneExpansion-Ports:noneI/O-Ports:noneClock:timerLength:5.8 inWidth:3.2 inHeight:0.7 to 1.3 inWeight:9 ozTemperature-Range:Operating:0 to 50 deg CCharging:10 to 40 deg CStorage:-40 to 55 deg CKeyboard:Switches:OFF / ONTIMER / PRGM / RUNShift-Keys:f, gold, above leftg, blue, above rightUser-Defined-Keys:noneKey-Arrangement::** ** ** ** **** ** ** ** **** ** ** ** ******* ** ** ***  *** *** ****  *** *** ****  *** *** ****  *** *** ***Key-Labels-Base-Keyboard:: x\GS+y1/x%BSTy^x<>yRvFIXSSTfgSTORCLGTOENTER^CHSEEXCLx-789+456x123\:-0.R/SKey-Labels-f-gold-above-left::\GS-sincostan[]L.R.lnlogSCI[][][]x-LAST xx\<=yH.MS+\v/xn!CLRDEGin->ft->gal->RADlbm->lbf->\^oF->GRDH->D->Btu->[]R->\pi[]Key-Labels-g-blue-above-right::[]sin-1cos-1tan-1[] x  x[]e10[][][][]s[]x=y 2H.MS-x[]CL.R[]<-mm<-m<-l[]<-kg<-N<-\^oC[]<-H.MS<-R<-J[]<-P[][]Programmable-Operations::%percent of+addition-subtraction0-9, .enter digit or decimal point1/xreciprocal10^xcommon exponentiation<-H.MSconvert to decimal hours<-Jconvert to BTU<-kgconvert to pounds of mass<-lconvert to gallons<-mconvert to feet<-mmconvert to inches<-Nconvert to pounds of force<-Pconvert to rectanglular<-Rconvert radians to degrees<-\^oCconvert to degrees FBtu->convert to JoulesCHSchange signCL.Rclear .0-.9 and the stackCLRclear 0-9 and the stackCLxclear Xcoscosinecos-1arc cosineD->convert degrees to radiansDEGset degrees modeEEXenter exponentENTER^entere^xnatural exponentiationFIX 0-9set FIX modeft->convert to metersgal->convert to litersGRDset grads modeGTO 00-50go to line numberH->convert to hours,minutes,secondsH.MS+hours,minutes,seconds additionH.MS-hours,minutes,seconds subtractionin->convert to millimetersL.R.compute linear regressionLAST xrecall last Xlbf->convert to Newtonslbm->convert to kilogramslnnatural logarithmlogcommon logarithmn!factorialR->convert to polarR/Srun / stopRADset radians modeRCL 0-9,.0-.9recall from a registerRvroll the stack downscompute standard deviationSCI 0-9set SCI modesinsinesin-1arc sineSTO +,-,x,\:- 0-9storage arithmetic (note all registers)STO 0-9,.0-.9store into a registertantangenttan-1arc tangentxmultiplicationx-compute meanx<>yswapx=y 00-50comparison test, implied go to line number if truex\<=y 00-50comparison test, implied go to line number if truex^2squarey^estimate yy^xpower\:-division\GS+add to statistics\GS-subtract from statistics\piconstant, value 3.141592654\v/xsquare root\^oF->convert to degrees CNon-Programmable-Operations::BSTback step, also clear prefixff-shiftgg-shiftSSTsingle stepTimer Mode:0-9stores current time in register (splits)EEXtoggle 1/100 sec displayR/Sstart / stop timerMenus::noneBugs/ROM-Versions::noneNotes::Shift keys are not merged in programs.Storage arithmetic does R op X and not X op R.