Added new PCB board and update README with the low mem modality

README.md

@@ -40,6 +40,33 @@ So to read all analog input in one trasmission you can do (even if I use  a 10mi
 	Serial.println(di.p3);
 ```
 
+To follow a request (you can see It on [issue #5](https://github.com/xreef/PCF8574_library/issues/5)) I create a define variable to work with low memori device, if you decomment this line on .h file of the library:
+
+```cpp
+// #define PCF8574_LOW_MEMORY
+```
+
+Enable low memory props and gain about 7byte of memory, and you must use the method to read all like so:
+
+ ```cpp
+	byte di = pcf8574.digitalReadAll();
+	Serial.print("READ VALUE FROM PCF: ");
+	Serial.println(di, BIN);
+```
+
+where di is a byte like 1110001, so you must do a bitwise operation to get the data, operation that I already do in the "normal" mode, here an example:
+
+ ```cpp
+	p0 = ((di & bit(0))>0)?HIGH:LOW;
+	p1 = ((di & bit(1))>0)?HIGH:LOW;
+	p2 = ((di & bit(2))>0)?HIGH:LOW;
+	p3 = ((di & bit(3))>0)?HIGH:LOW;
+	p4 = ((di & bit(4))>0)?HIGH:LOW;
+	p5 = ((di & bit(5))>0)?HIGH:LOW;
+	p6 = ((di & bit(6))>0)?HIGH:LOW;
+	p7 = ((di & bit(7))>0)?HIGH:LOW;
+ ```
+ 
 
 if you want read a single input:
 

resources/gcodeSimplePCF/border.gcode

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resources/gcodeSimplePCF/drill.gcode

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resources/gerberPCFRedIC/PCB_PCF8574_IC_contour.gm1

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resources/gerberPCFRedIC/PCB_PCF8574_IC_copperBottom.gbl

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resources/gerberPCFRedIC/PCB_PCF8574_IC_drill.txt

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resources/gerberPCFRedIC/PCB_PCF8574_IC_maskBottom.gbs

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resources/gerberPCFRedIC/PCB_PCF8574_IC_pnp.txt

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+*Pick And Place List
+*Company=
+*Author=
+*eMail=
+*
+*Project=PCB_PCF8574_IC
+*Date=19:04:35
+*CreatedBy=Fritzing 0.9.3b.04.19.5c895d327c44a3114e5fcc9d8260daf0cbb52806
+*
+*
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+6;;DIP (Dual Inline) [THT];17.5942;-12.3679;180;Bottom;IC1
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+12;;;6.16419;-21.2579;0;Bottom;Via6
+13;;;8.70418;-21.2579;0;Bottom;Jumper1
+14;;;11.2442;-13.6379;0;Bottom;Via9
+15;;;23.9442;-18.7179;0;Bottom;Via20
+16;;;23.9443;-6.01783;0;Bottom;Via13
+17;;;11.2442;-6.01792;0;Bottom;Via12
+18;;;11.2442;-26.3379;0;Bottom;Jumper2
+19;;;3.62419;-28.8779;0;Bottom;Via1
+20;;;17.3515;-10.6068;90;Bottom;TXT1
+21;;;23.9443;-3.47783;0;Bottom;Via15
+22;;;11.2442;-8.55792;0;Bottom;Via11
+23;;;7.50459;-6.05592;0;Bottom;TXT1