M706 PCB REV K SCHEMATIC REV L TELETYPE RECEIVER NOTE: 17 PINS not used 1 AA1 PAD, NOT CONNECTED 2 AB1 NOT CONNECTED 3 AC1 NOT CONNECTED 4 AU1 NOT CONNECTED 5 AB2 NOT CONNECTED 6 BA1 NOT CONNECTED 7 BB1 NOT CONNECTED 8 BC1 NOT CONNECTED 9 BE1 NOT CONNECTED 10 BF1 NOT CONNECTED 11 BH1 NOT CONNECTED 12 BJ1 NOT CONNECTED 13 BK1 NOT CONNECTED 14 BL1 PAD, NOT CONNECTED 15 BV1 PAD, NOT CONNECTED 16 BB2 NOT CONNECTED 17 BK2 NOT CONNECTED CPU schematics shows output TT SHIFT-N PINS 1 O AD1 +3V 2 I AL2 READ BUFFER (normally IOP4) 3 I AD2 (DEVICE SELECTOR BMB INPUTS) (nand)-> (DEVICE SELECT-N) 4 I AE1 (DEVICE SELECTOR BMB INPUTS) (nand)-> (DEVICE SELECT-N) 5 I AF1 (DEVICE SELECTOR BMB INPUTS) (nand)-> (DEVICE SELECT-N) 6 I AH1 (DEVICE SELECTOR BMB INPUTS) (nand)-> (DEVICE SELECT-N) 7 I AH2 (DEVICE SELECTOR BMB INPUTS) (nand)-> (DEVICE SELECT-N) 8 I AJ1 (DEVICE SELECTOR BMB INPUTS) (nand)-> (DEVICE SELECT-N) 9 I AP1 (FORCE SELECT-N) (normally HI) nand(DEVICE SELECT-N)=(SELECTED) 10 I BF2 I/O CLEAR (normally INITIALIZE) 11 I BJ2 CLEAR FLAG 1 (normally IOP2) 12 O BE2 (SELECTED IOP2-N) = CLEAR FLAG 1 nand (SELECTED) 13 I BD1 CLEAR FLAG 2 (normally connected to GROUND) 14 O AE2 (KCC-N) = (SELECTED IOP2) nor I/O CLEAR nor CLEAR FLAG 2 15 O AV1 BUFFER STROBE = READ BUFFER and (SELECTED) 16 I BM1 (EXTRA IN) (not used? on CPU schematic) 17 O BN1 (EXTRA-N) = (EXTRA IN) nand BUFFER STROBE 18 I BD2 SKP. STROBE (normally IOP1) 19 O AF2 FLAG-N (aka P.I. REQUEST) 20 O BH2 I/O SKIP = FLAG nand SKP. STROBE nand (SELECTED) (active LO) 21 I AV2 (READER RUN SET-N) (normally connected to (KCC-N)) 22 O BL2 READER RUN 23 O AU2 READER ENABLE cannot test (PNP hi driver; 26ma @1V; open (-15?) 24 O BN2 (ACTIVE-N) (aka IN ACTIVE on CPU schematic) 25 O BS2 (PRESET-N) = (200ns?) pulse on ACTIVE-N falling edge 26 I AN1 CLOCK 8 BAUD 27 O BS1 CLOCK SCALE 2-N (CLOCK 8 BAUD / 4) normally drives (STOP CLOCK) 28 O BT2 CLOCK SCALE 2 (CLOCK 8 BAUD divided by 4) 29 I BP2 (STOP CLOCK) (<-CLOCK SCALE 2-N for 0.5 stop; -P for x.0) 30 I BP1 (STOP SET-N) (normally +3?) 31 O BU2 STOP 1-N 32 O BV2 STOP 2-N (normally drives IN LAST UNIT) 33 I BR2 IN LAST UNIT CLEAR-N (<-STOP 1-N for 1.x stop; STOP 2-N for 2) 34 I BM2 TELETYPE SERIAL INPUT 35 O AM2 (TELETYPE SERIAL INPUT-N) 36 I BR1 ENABLE (normally +3V (33)) 37 I AR1 (TT0 DATA) (normally connected to (TELETYPE SERIAL INPUT-N) 38 O AK1 (TT2) (normally connected to AJ2 (TT3 DATA) for 8 bit data) 39 I AJ2 (TT3 DATA) =(DATA IN) for 5 bit; = (TT2) for 8 bit 40 I BU1 SHIFT CLOCK (normally CLOCK SCALE 2) 41 O AS1 TT SHIFT (100ns? pulse) aka SHIFT on CPU schematic 42 O AK2 TT0-N (MSB) = TT0 nand BUFFER STROBE 43 O AR2 TT1-N = TT0 nand BUFFER STROBE 44 O AS2 TT2-N = TT0 nand BUFFER STROBE 45 O AL1 TT3-N = TT0 nand BUFFER STROBE 46 O AM1 TT4-N = TT0 nand BUFFER STROBE 47 O AP2 TT5-N = TT0 nand BUFFER STROBE 48 O AT2 TT6-N = TT0 nand BUFFER STROBE 49 O AN2 TT7-N (LSB) = TT0 nand BUFFER STROBE OIIIIIIIIIIOIOOIOIOOIOOOOIOOIIOOIIOIIOIIOOOOOOOOO ; note COLUMN 21 PIN AU2 is PNP hi side driver; can not test ; I/O CLEAR hi ; (READER RUN SET-N) low to set READER RUN (not normal powerup) ; (STOP SET-N) low to set STOP 1 and STOP 2 (not normal powerup) ; IN LAST UNIT CLEAR-N low to clear CLOCK SCALE 1 and CLOCK SCALE 2 1000000011010000101101X11010000000101X00011111111 ; toggle TELETYPE SERIAL INPUT with I/O CLEAR active -> no change 10 ; have (TT0 DATA) track (TELETYPE SERIAL INPUT-N) 0 01 ; have (TT0 DATA) track (TELETYPE SERIAL INPUT-N) 1 ; ; undo the initial setup that is not normal powerup ; ; release I/O CLEAR; (KCC-N) goes hi 0 1 ; release (STOP SET-N) 1 ; release (READER RUN SET-N) 1 ; release IN LAST UNIT CLEAR-N 1 ; check that STOP 1, STOP 2 do not count when not ACTIVE ; clock (STOP CLOCK). since ACTIVE-N is 1; no count STOP 1; STOP 2 1 0 ; clock CLOCK 8 BAUD to set (CLOCK SCALE 0) 1 0 ; set/clear CLEAR FLAG 2; (KCC-N) goes lo/hi 10 01 ; ; check 'not selected' does not change ; set/clear READ BUFFER -> no change (not selected) 1 0 ; set/clear (EXTRA IN) -> no change (not selected) 1 0 ; set/clear CLEAR FLAG 1 -> no change (not selected) 1 0 ; set/clear SKP. STROBE -> no change (not selected) 1 0 ; ; forced select tests ; ; (FORCE SELECT-N) 0 ; set CLEAR FLAG 1 -> (SELECTED IOP2-N) lo; (KCC-N) lo 10 0 ; clear/set (FORCE SELECT-N) -> (SELECTED IOP2-N) hi/lo; (KCC-N) hi/lo 1 1 1 0 0 0 ; set READ BUFFER -> BUFFFER STROBE goes hi; TTn-N go to ?? 1 1 XXXXXXXX ; set (EXTRA IN) -. (EXTRA-N) goes lo 10 ; clear READ BUFFER -> BUFFER STROBE goes lo; (EXTRA-N) goes hi 0 0 1 11111111 ; set READ BUFFER -> BUFFER STROBE goes hi; (EXTRA-N) goes ho 1 1 0 XXXXXXXX ; set SKP. STROBE -> no change (flag is off) 1 ; remove force select -> (SELECTED IOP2-N),(KCC-N),(EXTRA-N) hi; BUFFER STROBE lo 1 1 10 1 11111111 ; ; check device select ; ; device select -> (SELECTED IOP2-N),(KCC-N),(EXTRA-N) lo; BUFFER STROBE hi 100000 110000 111000 111100 111110 111111 0 01 0 XXXXXXXX 011111 1 10 1 11111111 001111 000111 000011 000001 000000 111111 0 01 0 XXXXXXXX 011111 1 10 1 11111111 111111 0 01 0 XXXXXXXX 101111 1 10 1 11111111 111111 0 01 0 XXXXXXXX 110111 1 10 1 11111111 111111 0 01 0 XXXXXXXX 111011 1 10 1 11111111 111111 0 01 0 XXXXXXXX 111101 1 10 1 11111111 111111 0 01 0 XXXXXXXX 111110 1 10 1 11111111 111111 0 01 0 XXXXXXXX 000000 1 10 1 11111111 000001 000010 000011 000100 000101 000110 000111 001000 001001 001010 001011 001100 001101 001110 001111 010000 010001 010010 010011 010100 010101 010110 010111 011000 011001 011010 011011 011100 011101 011110 011111 100000 100001 100010 100011 100100 100101 100110 100111 101000 101001 101010 101011 101100 101101 101110 101111 110000 110001 110010 110011 110100 110101 110110 110111 111000 111001 111010 111011 111100 111101 111110 111111 0 01 0 XXXXXXXX ; remove CLEAR FLAG 1 while selected -> (SELECTED IOP2-N) hi; (KCC-N) hi 01 1 ; remove (EXTRA IN) -> (EXTRA-N) goes hi 01 ; remove READ BUFFER -> BUFFER STROBE lo; TTn-N go hi 0 0 11111111 ; deselect 000000 0 ; ; test the start bit detect gate ; ; verify each signal does not falsely start bit detect with START ENABLE hi ; ; make sure they are off 0 010 ; set/clear TELETYPE SERIAL INPUT -> no change ; set/clear ENABLE -> no change 1 0 10 01 ; set/clear CLOCK 8 BAUD -> no change 1 0 ; ; verify each signal inhibits start bit detect with START ENABLE hi ; ; set ENABLE -> no change 1 ; set/clear TELETYPE SERIAL INPUT -> no change 10 01 ; set/clear CLOCK 8 BAUD -> no change 1 0 ; clear ENABLE 0 ; set CLOCK 8 BAUD -> no change 1 ; set/clear TELETYPE SERIAL INPUT -> no change 10 01 ; clear CLOCK 8 BAUD -> no change 0 ; ; do START BIT detect ; ; set CLOCK 8 BAUD 1 ; set ENABLE 1 ; prestage (TT0 DATA) due to clock edge 0 ; set TELETYPE SERIAL INPUT -> ; READER RUN,ACTIVE-N,STOP 1-N,STOP 2-N go lo 0 0 11 10 ; select and READ BUFFER -> BUFFER STROBE hi, TTn-N go lo 1111111 1 1 00000000 ; set (TT5 DATA) to match TT6 1 ; CLOCK 8 BAUD to toggle CLOCK SCALE 2-N and CLOCK SCALE 2 0 1 0 1 0 101 0 1 0 1 0 1 0 110 ; leave CLOCK SCALE 2 set 0 1 0 1 0 1 0 101 ; (STOP CLOCK) does not change STOP 1, STOP 2 since ACTIVE 1 0 1 0 ; clear TELETYPE SERIAL INPUT (do a short START BT) 01 ; have (TT0 DATA) track (TELETYPE SERIAL INPUT-N) 1 ; SHIFT CLOCK to shift 1 (short START BIT sets SPIKE DETECTOR) ; note: ACTIVE-N goes hi AFTER rising edge due to SPIKE DETECTOR ; and CLOCK SCLE 2 gets cleared 1 10 1 1 00000000 0 ; ; receive a '00000000' character ; ; prestage (TT0 DATA) due to clock edge 0 ; set TELETYPE SERIAL INPUT (START BIT) -> ; READER RUN,ACTIVE-N,TT0-N go lo; STOP 1-N,STOP 2-N go hi ; note: (TT2) is value AFTER rising clock 0 0 11 10 0 ; CLOCK 8 BAUD to setup CLOCK SCALE 2-N lo; CLOCK SCALE 2 hi 0 1 0 1 0 1 0 101 ; toggle SHIFT CLOCK -> shift in a '00000000' character 1 10000000 0 1 11000000 0 0 1 11100000 ; clear (TT3 DATA) to match TT2 0 0 1 11110000 0 1 11111000 0 1 11111100 0 1 11111110 0 1 11111111 0 ; shift start bit into FLAG -> I/O SKIP lo, FLAG-N (aka P.I. REQUEST) lo 00 1 ; turn off READ BUFFER -> BUFFER STROBE lo, (TTn-N still hi) 0 0 1 1 ; disable SKP. STROBE -> I/O SKIP goes hi 0 1 ; on SHIFT CLOCK falling edge, ACTIVE-N hi 1 0 ; clear TELETYPE SERIAL INPUT (stop bit); set TT0 DATA 01 ; have (TT0 DATA) track (TELETYPE SERIAL INPUT-N) 1 1 0 1 0 ; IN LAST UNIT CLEAR-N -> CLOCK SCALE 2 lo; CLOCK SCALE 2-N hi 10 0 ; ; receive a '11111111' character ; ;;;;;;;;;;;;;;;;;;;;;; ; END