* SPICE netlist
Q3 N006 N010 0 0 2SCR554P
Q2 N008 N009 0 0 2SCR554P
Rmotor N007 N006 1
Lmotor N008 N007 .05
V1 N001 0 5 volt
Q4 N008 N004 N001 0 2SAR554P
Q1 N006 N005 N001 0 2SAR554P
R1 N010 N003 33
R2 N005 N003 33
R3 N004 N002 33
R4 N009 N002 33
D1 0 N006 D
D2 0 N008 D
D3 N006 N001 D
D4 N008 N001 D
V2 N003 0 PULSE(0 5 0 0 0 1 1 1)
V3 N002 0 PULSE(0 5 1 0 0 1 0 1) AC 5
.tran 10

* LTspice schematic (.asc)
Version 4
SHEET 1 1568 864
WIRE -320 -432 -784 -432
WIRE 288 -432 -320 -432
WIRE 384 -432 288 -432
WIRE 288 -352 288 -432
WIRE -320 -336 -320 -432
WIRE 64 -336 -48 -336
WIRE -560 -320 -672 -320
WIRE 64 -304 64 -336
WIRE 96 -304 64 -304
WIRE 112 -304 96 -304
WIRE 224 -304 192 -304
WIRE -560 -288 -560 -320
WIRE -496 -288 -560 -288
WIRE -384 -288 -416 -288
WIRE -192 -288 -256 -288
WIRE -48 -272 -48 -336
WIRE -672 -240 -672 -320
WIRE 96 -240 96 -304
WIRE 144 -240 96 -240
WIRE 224 -240 224 -304
WIRE 352 -240 352 -304
WIRE 352 -240 224 -240
WIRE -560 -224 -560 -288
WIRE -496 -224 -560 -224
WIRE -384 -208 -384 -288
WIRE -192 -208 -192 -288
WIRE -192 -208 -384 -208
WIRE 384 -176 384 -432
WIRE 656 -176 384 -176
WIRE -48 -160 -48 -192
WIRE -784 -112 -784 -432
WIRE -672 -96 -672 -160
WIRE 656 -80 656 -176
WIRE 656 -80 560 -80
WIRE 768 -80 656 -80
WIRE -320 -64 -320 -240
WIRE -272 -64 -320 -64
WIRE -112 -64 -272 -64
WIRE 16 -64 -32 -64
WIRE 208 -64 96 -64
WIRE 288 -64 288 -256
WIRE 288 -64 208 -64
WIRE -496 -32 -496 -224
WIRE -496 -32 -640 -32
WIRE 208 -32 208 -64
WIRE 480 -32 208 -32
WIRE 560 -32 560 -80
WIRE 768 -32 768 -80
WIRE -272 0 -272 -64
WIRE 432 0 -272 0
WIRE 144 48 144 -240
WIRE 144 48 -48 48
WIRE 480 64 480 -32
WIRE 704 64 480 64
WIRE 432 128 432 0
WIRE 560 128 560 32
WIRE 560 128 432 128
WIRE 704 128 704 64
WIRE 768 128 768 32
WIRE 768 128 704 128
WIRE 288 144 288 -64
WIRE -320 160 -320 -64
WIRE -48 160 -48 48
WIRE 64 160 -48 160
WIRE -640 176 -640 -32
WIRE -560 176 -640 176
WIRE 64 192 64 160
WIRE 112 192 64 192
WIRE 224 192 192 192
WIRE -560 208 -560 176
WIRE -496 208 -560 208
WIRE -384 208 -416 208
WIRE 560 224 560 128
WIRE 768 224 768 128
WIRE 560 336 560 288
WIRE 672 336 560 336
WIRE 768 336 768 288
WIRE 768 336 672 336
WIRE -784 400 -784 -32
WIRE -320 400 -320 256
WIRE -320 400 -784 400
WIRE -16 400 -320 400
WIRE 288 400 288 240
WIRE 288 400 -16 400
WIRE 672 400 672 336
WIRE 672 400 288 400
WIRE -16 432 -16 400
FLAG -16 432 0
FLAG -672 -96 0
FLAG -48 -160 0
SYMBOL npn -384 160 R0
SYMATTR InstName Q3
SYMATTR Value 2SCR554P
SYMBOL npn 224 144 R0
SYMATTR InstName Q2
SYMATTR Value 2SCR554P
SYMBOL res -16 -80 R90
SYMATTR InstName Rmotor
SYMATTR Value 1
SYMBOL ind 112 -80 R90
SYMATTR InstName Lmotor
SYMATTR Value .05
SYMBOL voltage -784 -128 R0
SYMATTR InstName V1
SYMATTR Value 5 volt
SYMBOL pnp 352 -256 R180
SYMATTR InstName Q4
SYMATTR Value 2SAR554P
SYMBOL pnp -256 -240 R180
SYMATTR InstName Q1
SYMATTR Value 2SAR554P
SYMBOL res -400 192 R90
SYMATTR InstName R1
SYMATTR Value 33
SYMBOL res -400 -304 R90
SYMATTR InstName R2
SYMATTR Value 33
SYMBOL res 208 -320 R90
SYMATTR InstName R3
SYMATTR Value 33
SYMBOL res 208 176 R90
SYMATTR InstName R4
SYMATTR Value 33
SYMBOL diode 576 288 R180
SYMATTR InstName D1
SYMBOL diode 784 288 R180
SYMATTR InstName D2
SYMBOL diode 576 32 R180
SYMATTR InstName D3
SYMBOL diode 784 32 R180
SYMATTR InstName D4
SYMBOL voltage -672 -256 R0
SYMATTR InstName V2
SYMATTR Value PULSE(0 5 0 0 0 1 1 1)
SYMBOL voltage -48 -288 R0
SYMATTR Value2 AC 5
SYMATTR InstName V3
SYMATTR Value PULSE(0 5 1 0 0 1 0 1)