Dynamic Shift Registers - Bitsavers - Trailing-Edge

operating characteristics (con'tl for programming operations(see Figure 4)PARAMETER CONDITIONS MIN TYP MAX UNITSDuty Cycle 2 %Program Pulse Width, t.ppw (Note 4) V DD ; V LL ; Vprogram ; -48V 20 msData Set Up Time, tDWData Hold Time, tDH11jJ.Sf.lsPulsed V LL and V DD Supply Overlap,tVD3 msOperation of the MM4203/MM5203 in Program ModeInitially, all 2048 bits of the MM4203/MM5203are in the HIGH state. Information is introducedby selectively programming LOWS in the properbit locations.Word address selection is done by the same decodingcircuitry used in the Read mode. The eightoutput terminals are used as data inputs to determinethe information pattern in the eight bits ofeach word. A LOW data input level (-50V) willleave a HIGH and a HIGH data input level willallow programming of a LOW. All eight bits of oneword are programmed simultaneously by settingthe desired bit information patterns on the datainput terminals. The duty cycle of the Programpulse (amplitude and width as specified on page 4).should be limited to 2%. The address should beapplied for at least 1 ps before application of theProgram pulse.During programming, all inputs are pulsed signals.MODEDATA AND ADDRESS LINESLOGIC 00,00 LOGIC "0 00Vss VBB voo PROGRAMRead (Data Out) Vss - 2.0 vss - 4.0Program (Data In) Vss -2.0 Vss - 40!Pulsel+5 +5 -12 +5GNO +12 -481 -48(Pulsel (PulselTape FormatThe custom patterns may be sent in on a Telex orsubmitted as a paper tape in a 7 bit ASCII codefrom model 33 teletype or TWX. The paper tapeshould be as the following example:A programmer specifically designed for theMM4203/MM5203 is available from: SpectrumDynamics, Inc., 2300 East Oakland Park Boulevard,Fort Lauderdale, Florida 33306.Start Character ---, Stop Character ---, Data Field MSB (Pin 11) LSB (Pin 4)Leader: Rubout for .. t I I + +TWf~:;e1el:t(~; I~:s~ B P P P N N N N N F B N N N N N N P P F ... B N P N P P P N N F25 frames') .. ~ ... ~Word aWord'Word 255All Address 1 nputs LOWAll Address Inputs HIGHTrailer: Rubout forT\tVX and letter Keyfor telex lat least25 frames')An output HIGH corresponds to a P on the papertape; an output LOW corresponds to an N.During programming, word 0 will cause -40V topunch tape formatO~~~O"3'000AnOIJ:nnOOO()f)(!~2Sp.~es -+---:;~~~7"'l~-g~~~~?~~ ~ -------~A004 00111]116 I ---1 SpaceNote L -_:gg~ ~g~.~(~~~g ~Alll"' 001111l1D 11AnOR OI1'lIlCl')()n (lA:,11 Oln llj 1 ("] 1 "rss 1 ",0 Note 4TB7 1 ':J1lTSh .,,50TRS "Of")Ta" () 1 f")TB3 InoTB2 299TBI t 197L_-=======:j-l Spacebe applied to all eight address inputs and word255 10 would cause 0 volts to be applied to alleight address inputs.Note 1: The code is a 7 bit ASCII code on 8 punch tape. The tapeshould begin and end with 25 or more "RUBOUT" punches.Note 2: The ROM input address is expressed in decimal form and ispreceded by the letter A.Note 3: The total number of "1's" bits in the output word.Note 4: The total number of "1's" bits in each output column orbit position.Note 5: Specify whether tape is positive true or negative true logic.Negative true is always assumed when not specified.The tape would print out as shown for the 256 x 8 code.69