Added reference files for SN74HC595 and ULN2803

reference/SN74HC595 - Serial in Parallel out 8-bit shift register.txt

@@ -0,0 +1,18 @@
+Pin   Assignment
+
+1     Q1
+2     Q2
+3     Q3
+4     Q4
+5     Q5
+6     Q6
+7     Q7
+8     GND   Ground
+9     Q7S   Serial output
+10    MR    Memory reset (low = reset)
+11    SHCP  Clock pulse
+12    STCP  Latch
+13    OE    Output enable (low = enabled)
+14    DS    Serial input
+15    Q0
+16    VCC

reference/ULN2803 Darlington Transistor Array.txt

@@ -0,0 +1,20 @@
+Pin   Assignment
+
+1     Base 1
+2     Base 2
+3     Base 3
+4     Base 4
+5     Base 5
+6     Base 6
+7     Base 7
+8     Base 8
+9     Ground
+10    Common cathode (for flyback diodes)
+11    Collector 8
+12    Collector 7
+13    Collector 6
+14    Collector 5
+15    Collector 4
+16    Collector 3
+17    Collector 2
+18    Collector 1