diff --git a/examples/keybrd_PCA9655E/keybrd_PCA9655E.ino b/examples/keybrd_PCA9655E/keybrd_PCA9655E.ino
index 522dc82..03441ef 100644
--- a/examples/keybrd_PCA9655E/keybrd_PCA9655E.ino
+++ b/examples/keybrd_PCA9655E/keybrd_PCA9655E.ino
@@ -37,7 +37,7 @@ PortIOE port_R1(1, 0);
 PortWrite_PCA9655E portWrite_R1(port_R1);
 
 PortIOE port_R0(0, 0);
-//PortWrite_PCA9655E portWrite_R0(port_R0); for LEDs
+//PortWrite_PCA9655E portWrite_R0(port_R0);     //for LEDs
 PortRead_PCA9655E portRead_R0(port_R0, 1<<0 | 1<<1 );
 
 Scanner_IOE scanner_R(HIGH, portWrite_R1, portRead_R0);
diff --git a/src/PortIOE.h b/src/PortIOE.h
index 83152a1..7ba4cf8 100644
--- a/src/PortIOE.h
+++ b/src/PortIOE.h
@@ -24,24 +24,13 @@ For example, I2C address with AD2=GND AD1=SCL AD0=SCL,
 http://playground.arduino.cc/Main/WireLibraryDetailedReference
 The PCA9655E data sheet is on http://www.onsemi.com/pub_link/Collateral/PCA9655E-D.PDF
 
-portNumber: If the I/O expander uses port letters, use 0 instead of A, use 1 instead of B.
-outputVal: For pins that are connected to active low rows, set outputVal bit to 1.
-           Set all other outputVal bits to 0.
-
-Example instantiation for port0 with active low rows on all pins:
-    PortIOE port0(0, ~0);
-
-Example instantiation for portA with active low rows on pins 0,1,2:
-    PortIOE portA(0, 1<<0 | 1<<1 | 1<<2 );
-
-Example instantiation for portB with active high rows on pins 0,1,2:
-    PortIOE portB(1, 0);
+portNumber: If the I/O expander uses port letters, use 0 inplace of A, use 1 inplace of B.
 */
 struct PortIOE
 {
     static const uint8_t DEVICE_ADDR;
     const uint8_t num;                          //port number
-    uint8_t outputVal;                          //bitwise value of output register
+    uint8_t outputVal;                          //bitwise value of output register for LEDs
 
     PortIOE(const uint8_t portNumber, uint8_t outputVal)
         : num(portNumber), outputVal(outputVal) {}
diff --git a/src/PortReadInterface.h b/src/PortReadInterface.h
index 5e3646f..c2c3cfd 100644
--- a/src/PortReadInterface.h
+++ b/src/PortReadInterface.h
@@ -12,7 +12,7 @@ Details are in config_key.h
 class PortReadInterface
 {
     public:
-        virtual void begin()=0;
+        virtual void begin(const uint8_t strobeOn)=0;
         virtual uint8_t read()=0;
 };
 #endif
diff --git a/src/PortRead_MCP23S17.cpp b/src/PortRead_MCP23S17.cpp
index d7e2b44..f04f1de 100644
--- a/src/PortRead_MCP23S17.cpp
+++ b/src/PortRead_MCP23S17.cpp
@@ -1,12 +1,10 @@
 #include "PortRead_MCP23S17.h"
 
 /*
-SPI bus is configured in PortWrite_MCP23S17::begin().
+begin() is called from Scanner_IOE::begin().
 */
 void PortRead_MCP23S17::begin(const uint8_t strobeOn)
 {
-    uint8_t pullUp;                             //bitwise, 1 means internal pull-up resistor enabled
-
     if (strobeOn == LOW)                        //if active low
     {
         pullUp = readPins;
@@ -16,25 +14,27 @@ void PortRead_MCP23S17::begin(const uint8_t strobeOn)
         pullUp = 0;
     }
 
+Keyboard.print("\npullUp=");//todo
+Keyboard.print(pullUp);
+/*
+    //todo these 4 lines are duplicated in PortWrite_MCP23S17::begin(), which is called first
     pinMode(SS, OUTPUT);                        //configure controller's Slave Select pin to output
     digitalWrite(SS, HIGH);                     //disable Slave Select
     SPI.begin();
     SPI.beginTransaction(SPISettings (SPI_CLOCK_DIV8, MSBFIRST, SPI_MODE0)); //control SPI bus todo is slow clock needed?
-
+    //SPI.endTransaction() not called to release SPI bus because keyboard only has one SPI device.
+*/
     digitalWrite(SS, LOW);                      //enable Slave Select
-      SPI.transfer(port.DEVICE_ADDR << 1);             //write command
+      SPI.transfer(port.DEVICE_ADDR << 1);      //write command
       SPI.transfer(port.num);                   //configure IODIR
       SPI.transfer(readPins);                   //0=output (for LED), 1=input (for read)
-    digitalWrite(SS, LOW);                      //enable Slave Select
+    digitalWrite(SS, HIGH);                     //enable Slave Select
 
-    digitalWrite(SS, HIGH);                     //disable Slave Select
-      SPI.transfer(port.DEVICE_ADDR << 1);             //write command
+    digitalWrite(SS, LOW);                      //disable Slave Select
+      SPI.transfer(port.DEVICE_ADDR << 1);      //write command
       SPI.transfer(port.num + 0x0C);            //configure GPPU
       SPI.transfer(pullUp);                     //0=pull-up disabled (for LED), 1=pull-up enabled (for read)
     digitalWrite(SS, HIGH);                     //disable Slave Select
-
-    //SPI.endTransaction() is not called to release the SPI bus
-    // because keyboard only has one SPI device.
 }
 
 /*
@@ -45,7 +45,7 @@ uint8_t PortRead_MCP23S17::read()
     uint8_t portState;                          //bit wise
 
     digitalWrite(SS, LOW);                      //enable Slave Select
-      SPI.transfer(port.DEVICE_ADDR << 1 | 1);         //read command
+      SPI.transfer(port.DEVICE_ADDR << 1 | 1);  //read command
       SPI.transfer(port.num + 0x12);            //GPIO register address to read data from
       portState = SPI.transfer(0);              //save the data (0 is dummy data to send)
     digitalWrite(SS, HIGH);                     //disable Slave Select
diff --git a/src/PortRead_MCP23S17.h b/src/PortRead_MCP23S17.h
index 8617bd0..dd81092 100644
--- a/src/PortRead_MCP23S17.h
+++ b/src/PortRead_MCP23S17.h
@@ -29,9 +29,11 @@ class PortRead_MCP23S17 : public PortReadInterface
 {
     private:
         PortIOE& port;
+        uint8_t pullUp;                         //bitwise, 1 means internal pull-up resistor enabled
         const uint8_t readPins;                 //bitwise, 1 means internal pull-up resistor enabled
     public:
-        PortRead_MCP23S17(PortIOE& port, const uint8_t readPins) : port(port), readPins(readPins) {}
+        PortRead_MCP23S17(PortIOE& port, const uint8_t readPins)
+            : port(port), readPins(readPins) {}
         void begin(const uint8_t strobeOn);
         virtual uint8_t read();
 };
diff --git a/src/PortRead_PCA9655E.cpp b/src/PortRead_PCA9655E.cpp
index cb210b6..a1ce08e 100644
--- a/src/PortRead_PCA9655E.cpp
+++ b/src/PortRead_PCA9655E.cpp
@@ -1,6 +1,8 @@
 #include "PortRead_PCA9655E.h"
 
-void PortRead_PCA9655E::begin()
+/*
+*/
+void PortRead_PCA9655E::begin(const uint8_t strobeOn)
 {
     Wire.beginTransmission(port.DEVICE_ADDR);
     Wire.write(port.num + 6);                   //configuration byte command
diff --git a/src/PortRead_PCA9655E.h b/src/PortRead_PCA9655E.h
index 836a680..490856c 100644
--- a/src/PortRead_PCA9655E.h
+++ b/src/PortRead_PCA9655E.h
@@ -33,7 +33,7 @@ class PortRead_PCA9655E : public PortReadInterface
     public:
         PortRead_PCA9655E (PortIOE& port, const uint8_t readPins)
             : port(port), readPins(readPins) {}
-        void begin();
+        void begin(const uint8_t strobeOn);
         virtual uint8_t read();
 };
 #endif
diff --git a/src/PortWriteInterface.h b/src/PortWriteInterface.h
index 9a04998..4b80bd0 100644
--- a/src/PortWriteInterface.h
+++ b/src/PortWriteInterface.h
@@ -13,6 +13,6 @@ class PortWriteInterface
 {
     public:
         virtual void begin()=0;
-        virtual void write(const uint8_t pin, const bool level)=0;
+        virtual void write(const uint8_t strobePin, const bool pinLogicLevel)=0;
 };
 #endif
diff --git a/src/PortWrite_MCP23S17.cpp b/src/PortWrite_MCP23S17.cpp
index 6d48ce2..2f0d6da 100644
--- a/src/PortWrite_MCP23S17.cpp
+++ b/src/PortWrite_MCP23S17.cpp
@@ -5,13 +5,13 @@
 void PortWrite_MCP23S17::writePort(const uint8_t registerAddr, const uint8_t data)
 {
     digitalWrite(SS, LOW);                      //enable Slave Select
-      SPI.transfer(port.DEVICE_ADDR << 1);             //write command
+      SPI.transfer(port.DEVICE_ADDR << 1);      //write command
       SPI.transfer(registerAddr);               //register address to write data to
       SPI.transfer(data);                       //data
     digitalWrite(SS, HIGH);                     //disable Slave Select
 }    
 
-/* begin() should be called once from sketch in setup().
+/* begin() is called from Scanner_IOE::begin().  Initiates SPI bus and configures write pins.
 PortRead_MCP23S17 and PortWrite_MCP23S17 should be on seperate ports on the same MCP23S17.
 Output pins can be used for strobe pins and LEDs.
 */
@@ -21,20 +21,18 @@ void PortWrite_MCP23S17::begin()
     digitalWrite(SS, HIGH);                     //disable Slave Select
     SPI.begin();
     SPI.beginTransaction(SPISettings (SPI_CLOCK_DIV8, MSBFIRST, SPI_MODE0)); //control SPI bus todo is slow clock needed?
+    //SPI.endTransaction() not called to release SPI bus because keyboard only has one SPI device.
 
     writePort(port.num, 0);                     //configure port direction (port.num) to output (0)
-
-    //SPI.endTransaction() is not called to release the SPI bus
-    // because keyboard only has one SPI device.
 }
 
 /*
 strobePin is bitwise, where pin being strobed is 1.
 pinLogicLevel is HIGH or LOW.
 port.outputVal can be shared by LEDs.
-The functions does not reset the other pins so that they can be used for LEDs.
+The function does not reset the other pins so that they can be used for LEDs.
 */
-void PortWrite_MCP23S17::write(const uint8_t strobePin, const uint8_t pinLogicLevel)
+void PortWrite_MCP23S17::write(const uint8_t strobePin, const bool pinLogicLevel)
 {
     if (pinLogicLevel == LOW)
     {
@@ -45,5 +43,5 @@ void PortWrite_MCP23S17::write(const uint8_t strobePin, const uint8_t pinLogicLe
         port.outputVal |= strobePin;            //set strobePin output to high
     }
 
-    writePort(port.num + 0x12, port.outputVal);  //set GPIO port pins for stobe and LEDs
+    writePort(port.num + 0x12, port.outputVal); //set GPIO port pins for strobe and LEDs
 }
diff --git a/src/PortWrite_MCP23S17.h b/src/PortWrite_MCP23S17.h
index e09e2f9..9d5fe13 100644
--- a/src/PortWrite_MCP23S17.h
+++ b/src/PortWrite_MCP23S17.h
@@ -43,6 +43,6 @@ class PortWrite_MCP23S17 : public PortWriteInterface
     public:
         PortWrite_MCP23S17(PortIOE& port) : port(port) {}
         void begin();
-        virtual void write(const uint8_t pin, const uint8_t level);
+        virtual void write(const uint8_t pin, const bool pinLogicLevel);
 };
 #endif
diff --git a/src/PortWrite_PCA9655E.cpp b/src/PortWrite_PCA9655E.cpp
index 4ed9aef..5c23fdb 100644
--- a/src/PortWrite_PCA9655E.cpp
+++ b/src/PortWrite_PCA9655E.cpp
@@ -6,6 +6,8 @@ Otherwise readPins could be overwritten.
 */
 void PortWrite_PCA9655E::begin()
 {
+    Wire.begin();
+
     Wire.beginTransmission(port.DEVICE_ADDR);
     Wire.write(port.num + 6);                   //configuration byte command
     Wire.write(0);                              //0=configure as output (for strobe pins and LED)
@@ -13,20 +15,20 @@ void PortWrite_PCA9655E::begin()
 }
 
 /*
-pin is bitwise, where pin being strobed is 1.
-value is HIGH or LOW.
+strobePin is bitwise, where pin being strobed is 1.
+pinLogicLevel is HIGH or LOW.
 Does not reset the other pins because LEDs could be using some of the pins.
 Syntax is similar to Arduino DigitalWrite().
 */
-void PortWrite_PCA9655E::write(const uint8_t pin, const bool value)
+void PortWrite_PCA9655E::write(const uint8_t strobePin, const bool pinLogicLevel)
 {
-    if (value == LOW)                           //if active low
+    if (pinLogicLevel == LOW)                   //if strobePin low
     {
-        port.outputVal &= ~pin;                 //set pin output to low
+        port.outputVal &= ~strobePin;           //set pin output to low
     }
-    else                                        //if active high
+    else                                        //if strobestrobe high
     {
-        port.outputVal |= pin;                  //set pin output to high
+        port.outputVal |= strobePin;            //set pin output to high
     }
 
     Wire.beginTransmission(port.DEVICE_ADDR);
diff --git a/src/PortWrite_PCA9655E.h b/src/PortWrite_PCA9655E.h
index ce797e6..bbd041a 100644
--- a/src/PortWrite_PCA9655E.h
+++ b/src/PortWrite_PCA9655E.h
@@ -41,6 +41,6 @@ class PortWrite_PCA9655E : public PortWriteInterface
         PortWrite_PCA9655E(PortIOE& port) : port(port) {}
         void begin();
 
-        virtual void write(const uint8_t pin, const bool level);
+        virtual void write(const uint8_t strobePin, const bool pinLogicLevel);
 };
 #endif
diff --git a/src/Scanner_IOE.cpp b/src/Scanner_IOE.cpp
index 79fe0a3..ffeb7af 100644
--- a/src/Scanner_IOE.cpp
+++ b/src/Scanner_IOE.cpp
@@ -1,22 +1,22 @@
 #include "Scanner_IOE.h"
 
-/* Row constructor calls every Scanner's init().
+/* init() is called once for each row from Row constructor.
 */
 void Scanner_IOE::init(const uint8_t strobePin)
 {
-    //emty function
+    //empty
 }
 
 /* begin() should be called once from sketch setup().
 */
 void Scanner_IOE::begin()
 {
-    Wire.begin();
-    refPortWrite.begin();
-    refPortRead.begin();
+    refPortWrite.begin();                       //configures SPI bus
+    refPortRead.begin(strobeOn);
 }
 
-/* scan() strobes the row's strobePin and retuns state of port's input pins.
+/* scan() is called on every iteration of sketch loop().
+scan() strobes the row's strobePin and retuns state of port's input pins.
 Bitwise variables are 1 bit per key.
 */
 read_pins_t Scanner_IOE::scan(const uint8_t strobePin)
@@ -33,5 +33,9 @@ read_pins_t Scanner_IOE::scan(const uint8_t strobePin)
     //strobe off
     refPortWrite.write(strobePin, strobeOff);
 
+    if (strobeOn == LOW)                        //if active low
+    {
+        readState = ~readState;
+    }
     return readState;
 }
diff --git a/src/Scanner_IOE.h b/src/Scanner_IOE.h
index def15f9..27dedda 100644
--- a/src/Scanner_IOE.h
+++ b/src/Scanner_IOE.h
@@ -3,7 +3,6 @@
 
 #include <Arduino.h>
 #include <inttypes.h>
-#include <Wire.h>
 #include <ScannerInterface.h>
 #include <PortWriteInterface.h>
 #include <PortReadInterface.h>
diff --git a/src/Scanner_ShiftRegsPISOSingleRow.h b/src/Scanner_ShiftRegsPISOSingleRow.h
index 1483659..00ce8d2 100644
--- a/src/Scanner_ShiftRegsPISOSingleRow.h
+++ b/src/Scanner_ShiftRegsPISOSingleRow.h
@@ -21,7 +21,7 @@ The Row "strobePin" parameter is ignored.
 In the above example, the "strobePin" argument is 0, but it doesn't matter what value is given.
 
 There are three Scanner_ShiftRegsPISOSingleRow parameters.
-"strobeOn" paramter is active state HIGH or LOW.
+"strobeOn" paramter is ignored, but should be active state HIGH or LOW required by ScannerInterface.
 
 "slaveSelect" paramter can be any controller pin connected to shift register's SHIFT-LOAD pin.
 slaveSelect pin SS (Arduino pin 10) has the fastest scan.
diff --git a/src/Scanner_uC.cpp b/src/Scanner_uC.cpp
index 6d4e874..30d7875 100644
--- a/src/Scanner_uC.cpp
+++ b/src/Scanner_uC.cpp
@@ -39,7 +39,8 @@ void Scanner_uC::init(const uint8_t strobePin)
     pinMode(strobePin, OUTPUT);
 }
 
-/* scan() strobes the row's strobePin and retuns state of readPins.
+/* scan() is called on every iteration of sketch loop().
+scan() strobes the row's strobePin and retuns state of readPins.
 Bitwise variables are 1 bit per key.
 */
 read_pins_t Scanner_uC::scan(const uint8_t strobePin)
diff --git a/src/config_keybrd.h b/src/config_keybrd.h
index a87d01a..21f19ef 100644
--- a/src/config_keybrd.h
+++ b/src/config_keybrd.h
@@ -13,9 +13,9 @@ Using smaller types on a 32-bit uC (Teensy LC) would accomplish nothing.
     For Scanner_ShiftRegs74HC165, Scanner_ShiftRegs74HC165::readPinCount
     For Scanner_IOE, cover the last 1 bit in Scanner_IOE::strobePin
 */
-typedef uint8_t read_pins_t;
+//typedef uint8_t read_pins_t;
 //typedef uint16_t read_pins_t;
-//typedef uint32_t read_pins_t;
+typedef uint32_t read_pins_t;
 
 /* SAMPLE_COUNT_MACRO is used in Debouncer_Samples.h
 SAMPLE_COUNT_MACRO = 4 is very reliable for a keyboard.
diff --git a/tutorials/keybrd_4c_split_with_IOE/keybrd_4c_split_with_IOE.ino b/tutorials/keybrd_4c_split_with_IOE/keybrd_4c_split_with_IOE.ino
index 5df249d..0e19e6d 100644
--- a/tutorials/keybrd_4c_split_with_IOE/keybrd_4c_split_with_IOE.ino
+++ b/tutorials/keybrd_4c_split_with_IOE/keybrd_4c_split_with_IOE.ino
@@ -2,11 +2,6 @@
 
 | Left  | **0** | **1** | | Right | **0** | **1** |
 |:-----:|-------|-------| |:-----:|-------|-------|
-| **0** | a     | b     | | **0** | 1     | 2     |
-| **1** | shift | c     | | **1** | 3     | shift |
-
-| Left  | **0** | **1** | | Right | **0** | **1** | todo
-|:-----:|-------|-------| |:-----:|-------|-------|
 | **1** |   1   |   2   | | **1** |   3   |   4   |
 | **0** |   a   |   b   | | **0** |   c   |   d   |
 */
@@ -14,79 +9,74 @@
 // ================= INCLUDES ==================
 #include <ScanDelay.h>
 #include <Code_Sc.h>
+#include <Row.h>
 
 //left matrix
-#include <Row_uC.h>
+#include <Scanner_uC.h>
 
 //right matrix
-#include <Row_IOE.h>
 #include <PortIOE.h>
 #include <PortWrite_MCP23S17.h>
 #include <PortRead_MCP23S17.h>
+#include <Scanner_IOE.h>
 
 // ============ SPEED CONFIGURATION ============
 ScanDelay scanDelay(9000);
 
-// ================ LEFT MATRIX ================
-// ---------------- ACTIVE STATE ---------------
-const bool Scanner_uC::STROBE_ON = LOW;         //active low
-const bool Scanner_uC::STROBE_OFF = HIGH;
-
-// ------------------- PINS --------------------
+// ================ LEFT SCANNER ===============
 uint8_t readPins[] = {14, 15};
+uint8_t readPinCount = sizeof(readPins)/sizeof(*readPins);
 
-// ================ RIGHT MATRIX ===============
-const bool Scanner_Port::STROBE_ON = HIGH;      //active high
-const bool Scanner_Port::STROBE_OFF = LOW;
+Scanner_uC scanner_L(LOW, readPins, readPinCount);
 
-const uint8_t PortIOE::DEVICE_ADDR = 0x18;
+// =============== RIGHT SCANNER ===============
+const uint8_t PortIOE::DEVICE_ADDR = 0x20;      //MCP23S17 address, all 3 ADDR pins are grounded
 
-// ------------------ PORT 1 -------------------
-PortIOE port1_R(1, 0);
-PortWrite_MCP23S17 portWrite1_R(port1_R);
+PortIOE port_A(0, 0);
+PortRead_MCP23S17 portRead_A(port_A, 1<<0 | 1<<1 );
 
-// ------------------ PORT 0 -------------------
-PortIOE port0_R(0, 0);
-PortWrite_MCP23S17 portWrite0_R(port0_R);
-PortRead_MCP23S17 portRead0_R(port0_R, 1<<0 | 1<<1 );
+PortIOE port_B(1, 0);
+//PortWrite_MCP23S17 portWrite_B(port_B);     //for LEDs
+PortWrite_MCP23S17 portWrite_B(port_B);
+
+Scanner_IOE scanner_R(LOW, portWrite_B, portRead_A);
 
 // =================== CODES ===================
-Code_Sc s_shiftL(MODIFIERKEY_LEFT_SHIFT);
-Code_Sc s_shiftR(MODIFIERKEY_RIGHT_SHIFT);
-
 Code_Sc s_a(KEY_A);
 Code_Sc s_b(KEY_B);
 Code_Sc s_c(KEY_C);
+Code_Sc s_d(KEY_D);
+
 Code_Sc s_1(KEY_1);
 Code_Sc s_2(KEY_2);
 Code_Sc s_3(KEY_3);
+Code_Sc s_4(KEY_4);
 
 // =================== ROWS ====================
 // ---------------- LEFT ROWS ------------------
-Key* ptrsKeys_L0[] = { &s_a, &s_b };
+Key* ptrsKeys_L0[] = { &s_1, &s_2 };
 const uint8_t KEY_COUNT_L0 = sizeof(ptrsKeys_L0)/sizeof(*ptrsKeys_L0);
-Row_uC row_L0(0, readPins, KEY_COUNT_L0, ptrsKeys_L0);
+Row row_L0(scanner_L, 0, ptrsKeys_L0, KEY_COUNT_L0);
 
-Key* ptrsKeys_L1[] = { &s_c,  &s_shiftL };
+Key* ptrsKeys_L1[] = { &s_a, &s_b };
 const uint8_t KEY_COUNT_L1 = sizeof(ptrsKeys_L1)/sizeof(*ptrsKeys_L1);
-Row_uC row_L1(1, readPins, KEY_COUNT_L1, ptrsKeys_L1);
+Row row_L1(scanner_L, 1, ptrsKeys_L1, KEY_COUNT_L1);
 
 // ---------------- RIGHT ROWS -----------------
-Key* ptrsKeys_R0[] = { &s_1, &s_2 };
+Key* ptrsKeys_R0[] = { &s_3, &s_4 };
 const uint8_t KEY_COUNT_R0 = sizeof(ptrsKeys_R0)/sizeof(*ptrsKeys_R0);
-Row_IOE row_R0(portWrite1_R, 1<<0, portRead0_R, KEY_COUNT_R0, ptrsKeys_R0);
+Row row_R0(scanner_R, 1<<0, ptrsKeys_R0, KEY_COUNT_R0);
 
-Key* ptrsKeys_R1[] = { &s_3,  &s_shiftR };
+Key* ptrsKeys_R1[] = { &s_c,  &s_d };
 const uint8_t KEY_COUNT_R1 = sizeof(ptrsKeys_R1)/sizeof(*ptrsKeys_R1);
-Row_IOE row_R1(portWrite1_R, 1<<1, portRead0_R, KEY_COUNT_R1, ptrsKeys_R1);
+Row row_R1(scanner_R, 1<<1, ptrsKeys_R1, KEY_COUNT_R1);
 
 // ################### MAIN ####################
 void setup()
 {
+delay(7000); //todo
     Keyboard.begin();
-    Wire.begin();                               //Wire.begin() must be called before port begin()
-    portWrite1_R.begin();
-    portRead0_R.begin();
+    scanner_R.begin();
 }
 
 void loop()
@@ -102,4 +92,5 @@ void loop()
     scanDelay.delay();
     //debug.print_scans_per_second();
     //debug.print_microseconds_per_scan();
+delay(100); //todo
 }
diff --git a/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17.ino b/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17.ino
index 1886c50..88a3db6 100644
--- a/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17.ino
+++ b/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17.ino
@@ -1,18 +1,14 @@
 /* unit test for PortRead_MCP23S17
+Picture of hardware is in unit_tests/PortRead_MCP23S17/PortRead_MCP23S17_bb.JPG
 The setup is an MCP23S17 I/O expander on a Teensy LC controller.
 MCP23S17 port-B pins are alternately grounded and energized.
 portBState is a bitwise reading of port B.
 output is: 10101010
-
-posted on http://arduino.stackexchange.com/questions/tagged/spi
-http://arduino.stackexchange.com/questions/28792/reading-an-mcp23s17-i-o-expander-port-with-the-arduino-spi-library
 */
+
 #include "PortIOE.h"
 #include "PortRead_MCP23S17.h"
-#include "Scanner_Port.h"
-
-const bool Scanner_Port::STROBE_ON = LOW;
-const bool Scanner_Port::STROBE_OFF = HIGH;
+#include "Scanner_IOE.h"
 
 const uint8_t PortIOE::DEVICE_ADDR = 0x20;      //MCP23S17 address, all 3 ADDR pins are grounded
 PortIOE portB(1, 0);
@@ -24,7 +20,7 @@ void setup()
     uint8_t portBState;                         //bit wise
 
     delay(6000);
-    portBRead.begin();
+    portBRead.begin(LOW);
 
     portBState = portBRead.read();
     Keyboard.print("portBState = ");
diff --git a/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17_bb.JPG b/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17_bb.JPG
new file mode 100644
index 0000000..9153e5c
Binary files /dev/null and b/unit_tests/PortRead_MCP23S17/PortRead_MCP23S17_bb.JPG differ
diff --git a/unit_tests/PortWrite_MCP23S17/PortRead_MCP23S17.ino b/unit_tests/PortWrite_MCP23S17/PortWrite_MCP23S17.ino
similarity index 78%
rename from unit_tests/PortWrite_MCP23S17/PortRead_MCP23S17.ino
rename to unit_tests/PortWrite_MCP23S17/PortWrite_MCP23S17.ino
index dc4cb3f..4aa1566 100644
--- a/unit_tests/PortWrite_MCP23S17/PortRead_MCP23S17.ino
+++ b/unit_tests/PortWrite_MCP23S17/PortWrite_MCP23S17.ino
@@ -1,9 +1,10 @@
-/* unit test for PortRead_MCP23S17
+/* unit test for PortWrite_MCP23S17
+Picture of hardware is in unit_tests/PortRead_MCP23S17/PortRead_MCP23S17_bb.JPG
 The setup is an MCP23S17 I/O expander on a Teensy LC controller.
 MCP23S17 port-A GPIO pins are not connected to anything.
 Port-A GPIO-pin ouputs alternate between 0 and 3.3 volts.
 
-Use a volt meter to measure port-A GPIO-pin ouputs.
+Use a volt meter to measure port-A GPIO-pin outputs.
 MCP23S17 on 3.3v does not output enough power to reliable light LEDs
     LED lights w/o resistor
     LED not light with 56 ohm resistor
@@ -16,7 +17,7 @@ PortIOE portA(0, 0);
 
 PortWrite_MCP23S17 portAWrite(portA);           //PortAWrite needed for begin()
 
-const uint8_t GPIOA = 0x12;                     //LEDs are on port A
+//const uint8_t GPIOA = 0x12;                     //LEDs are on port A
 
 void setup()
 {