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diff --git a/digital-driver-board/firmware/TinyWire-master/TinyWireS/examples/TinyWireS_Stress_Slave/TinyWireS_Stress_Slave.ino b/digital-driver-board/firmware/TinyWire-master/TinyWireS/examples/TinyWireS_Stress_Slave/TinyWireS_Stress_Slave.ino
new file mode 100644
index 0000000..c7fbe41
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+++ b/digital-driver-board/firmware/TinyWire-master/TinyWireS/examples/TinyWireS_Stress_Slave/TinyWireS_Stress_Slave.ino
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+// ---------------------------------
+// Stress test program/example for TinyWireS I2C library.
+// Run this slave program on the Attiny.
+// Run the other master program on the Arduino Uno R3.
+// ---------------------------------
+// // Written by Scott Hartog, 2/6/2016, to stress test the TinyWireS library.
+// https://github.com/rambo/TinyWire
+//
+// This project uses the Tiny85 as an I2C slave.
+//
+// The slave program using TinyWireS, running on a Attiny85, receives
+// N bytes of random data in a single receiveEvent() callback and
+// stores that data in a global buffer. It then responds the first requestEvent()
+// callback with that same data. The requestEvent() callback overwrites the data
+// buffer with zeros after responding so it will only respond correctly to the
+// first requestEvent() callback after each receiveEvent() callback. Subsequent
+// requestEvent() will respond with 0xff for all data bytes.
+//
+//
+// SETUP:
+// AtTiny Pin 5 (PB0/SDA) = I2C SDA 
+//     connect to SDA on master with external pull-up (~4.7K)
+// AtTiny Pin 7 (PB0/SCL) = I2C SCL 
+//     connect to SCL on master with external pull-up (~4.7K)
+// AtTiny Pin 1 (PB5/!RST)
+//     connect to reset on master (or just pull-up)
+//
+// Please see credits and usage for usiTwiSlave and TinyWireS in the .h files of 
+// those libraries.
+
+#include <avr/sleep.h>
+#include <avr/wdt.h>
+#include "TinyWireS.h"                  // wrapper class for I2C slave routines
+
+#define I2C_SLAVE_ADDR  0x26            // i2c slave address (38, 0x26)
+
+// turns on code that makes the Tiny85 sleep between transactions
+// This is optional. The Tiny85 current drops from
+// about 2mA to about 20uA when the CPU is put into
+// PowerDown sleep mode.
+#define USE_CPU_SLEEP
+
+// global buffer to store data sent from the master.
+uint8_t master_data[16];
+// global variable to number of bytes sent from the master.
+uint8_t master_bytes;
+
+// Gets called when the ATtiny receives an i2c write slave request
+// This routine runs from the usiTwiSlave interrupt service routine (ISR)
+// so interrupts are disabled while it runs.
+void receiveEvent(uint8_t num_bytes)
+{
+  uint8_t i;
+
+  // save the number of bytes sent from the master
+  master_bytes = num_bytes;
+
+  // store the data from the master into the data buffer
+  for (i = 0; i < master_bytes; i++)
+    master_data[i] = TinyWireS.receive();
+    
+}
+
+// Gets called when the ATtiny receives an i2c read slave request
+// This routine runs from the usiTwiSlave interrupt service routine (ISR)
+// so interrupts are disabled while it runs.
+void requestEvent()
+{
+  uint8_t i;
+  
+  // send the data buffer back to the master
+  for (i = 0; i < master_bytes; i++)
+    TinyWireS.send(master_data[i]);
+
+  // corrupt the byte values in the data buffer
+  // so that any subsequent call won't match
+  for (i = 0; i < master_bytes; i++)
+    master_data[i] += 0x5a;
+
+  // corrupt length of the request, but don't make it zero
+  
+  // if the usiTwiSlave.c is working fine, then this number is completely irrelevant
+  // because the requestEvent() callback will not be called again until
+  // after the next receiveEvent() callback, so the master_data and
+  // master_bytes variables will be overwritten by that call.
+
+  // If the usiTwiSlave.c has the issue of calling the requestFrom() callback
+  // for each byte sent, the buffer will accumulate by this amount *for each byte
+  // in the original request*. (This problem is fixed in the recent version.)
+  // 
+  // Making it zero will obscure the 1-byte send issue in the usiTwiSlave.c
+  // that is being tested.
+  // Making it small will allow a few requests to succeed before the tx buffer
+  // overflows and the usiTwiSlave.c hangs on the "while ( tmphead == txTail );"
+  // line
+  master_bytes = 2; 
+}
+
+void setup()
+{
+  //pinMode(1,OUTPUT);   // This pin can be used for rudimentary debug
+  
+  // initialize the TinyWireS and usiTwiSlave libraries
+  TinyWireS.begin(I2C_SLAVE_ADDR);      // init I2C Slave mode
+
+  // register the onReceive() callback function
+  TinyWireS.onReceive(receiveEvent);
+  
+  // register the onRequest() callback function
+  TinyWireS.onRequest(requestEvent);
+
+ // disable the watchdog timer so that it doesn't
+  // cause power-up, code is from datasheet
+  // Clear WDRF in MCUSR – MCU Status Register
+  // MCUSR provides information on which reset source caused an MCU Reset.
+  MCUSR = 0x00;
+  // WDTCR - Watchdog Timer Control Register
+  // Write logical one to WDCE and WDE (must be done before disabling)
+  WDTCR |= ( _BV(WDCE) | _BV(WDE) );
+  // Turn off WDT
+  WDTCR = 0x00;
+
+#ifdef USE_CPU_SLEEP
+  // enable power down sleep mode
+  set_sleep_mode(SLEEP_MODE_PWR_DOWN);  // sleep mode
+  sleep_enable();
+#endif
+
+  sei();                                // enable interrupts
+
+}
+
+void loop()
+{
+
+#ifdef USE_CPU_SLEEP
+  // optionally put the CPU to sleep. It will be woken by a USI interrupt
+  // when it sees a "start condition" on the I2C bus. Everything interesting
+  // happens in the usiTwiSlave ISR.
+  sleep_cpu();
+#endif
+
+}