diff --git a/demo/interrupt.js b/demo/interrupt.js
index e5db5bc..74dceb9 100644
--- a/demo/interrupt.js
+++ b/demo/interrupt.js
@@ -21,23 +21,33 @@ let pinB = 16
 
 let id = `${CHIP} at I2C bus address of 0x${ADDR.toString(16)}`
 
-async function ihandler(port) {
-	let pin = await this.interruptPin(port, 'PLC')
-	console.log(`handler fired for ${this.id} on port ${port} pin ${pin}`)
-	await this.interruptReset(port)
-}
-
 let mcp = new MCP[CHIP](bus, ADDR, {
 	pin_cfg_default: 'toggle_switch',
 	id: id,
 	interruptA: new Interrupt(pinA, ihandler),
-	interruptB: new Interrupt(pinB, ihandler)
-});
+	interruptB: new Interrupt(pinB, ihandler),
+	stateA: 128,
+	pidsA: ['sw1', 'sw2', 'sw3', 'sw4', 'sw5', 'sw6', 'sw7', 'sw8'],
+	pidsB: ['sw9', 'sw10', 'sw11', 'sw12', 'sw13', 'sw14', 'sw15', 'sw16']
+}); // must have ; for async immediate function following
 
 (async function () {
 
 	await mcp.init()
-	// start will start the
 	await mcp.start()
 
+	mcp.on('fired', (data) => {
+		console.log(`bank event 'fired' data => ${data.bank} on port ${data.port} pin# ${data.pin} pid ${data.pid}`)
+	})
+
 })()
+
+//=================================//
+
+async function ihandler(port) {
+	let pin = await this.interruptPin(port, 'PLC')
+	await this.interruptReset(port)
+	let data = { bank: this.id, port: port, pin: pin, pid: this.pid(pin, port) }
+	// console.log('data in handler', data)
+	return data
+}
diff --git a/demo/sample.js b/demo/sample.js
index 97d0c50..ce85a6d 100644
--- a/demo/sample.js
+++ b/demo/sample.js
@@ -21,7 +21,7 @@ let mcp = new MCP[CHIP](bus, ADDR);
 	await pause(MS)
 
 	let pins = [1, 7, 8]
-	await mcp.on(pins, PORT, 'PLC')
+	await mcp.pinsOn(pins, PORT, 'PLC')
 	let result = await mcp.readPort(PORT, { format: 'PLC' })
 	console.log(`${pins} on = current state: ${result.sort()}`)
 	await pause(MS)
@@ -33,7 +33,7 @@ let mcp = new MCP[CHIP](bus, ADDR);
 	await pause(MS)
 
 	pins = [2, 1, 7]
-	await mcp.off(pins, PORT, 'PLC')
+	await mcp.pinsOff(pins, PORT, 'PLC')
 	result = await mcp.readPort(PORT, { format: 'PLC' })
 	console.log(`${pins} off = current state: ${result.sort()}`)
 	await pause(MS)
diff --git a/package.json b/package.json
index c75962a..b177fe8 100644
--- a/package.json
+++ b/package.json
@@ -29,8 +29,9 @@
   },
   "homepage": "https://github.com/uCOMmandIt/uci-mcp#readme",
   "dependencies": {
-    "@uci/i2c": "0.0.1",
-    "@uci/utils": "0.0.1"
+    "@uci/i2c": "^0.1.0",
+    "@uci/utils": "^0.1.0",
+    "aggregation": "^1.2.0"
   },
   "devDependencies": {
     "chai": "^3.5.0",
diff --git a/src/mcp23008-17.js b/src/mcp23008-17.js
index db8f7c0..4632008 100644
--- a/src/mcp23008-17.js
+++ b/src/mcp23008-17.js
@@ -2,7 +2,9 @@
 
 const Device = require('@uci/i2c').Device,
 	portpin = require('./port-pin'), // classes for MCP port and pins
-	_ = require('@uci/utils')
+	EventEmitter = require('events'),
+	_ = require('@uci/utils'),
+	aggregate = require("aggregation/es6")
 
 const
 	Port = portpin.Port,
@@ -10,7 +12,7 @@ const
 	pause = _.pPause,
 	debug = _.debug('mcp:23008-17')
 
-class MCP23008 extends Device {
+class MCP23008 extends aggregate(Device, EventEmitter) {
 	constructor(busObj, i2cAddress, opts = {}) {
 		super(busObj, i2cAddress, opts)
 		// opts could include options passed on to ports and pin  including custom pin config, pin ids...see gpio.js
@@ -50,9 +52,12 @@ class MCP23008 extends Device {
 		debug.L1(`\n=======\nInitializing ${this.id}`)
 		await this.writeChipCfg(this.chip_config) // chip settings
 		await this.writePinsCfg()
-		// write out any loaded state
+		// write out any initial  state(s)
 		for (let port in this.ports) {
-			await this.writePort(this.state(port), 'force', port)
+			if (this.state(port)) {
+				debug.L1(`writing initial port state ${port} ${this.state(port)}`)
+				await this.writePort(this.state(port), 'force', port)
+			}
 		}
 	}
 
@@ -69,14 +74,18 @@ class MCP23008 extends Device {
 
 	async startInterrupt(port) {
 		await this.interruptReset(port)
+		debug.L1(`starting interrupt on port ${ port }`)
 		await this.inter(port).start()
+		let chip = this // scope `this` for use in the listener below
 		// bind handler to the chip so handler can read/write to chip/bank when interrupt is emitted
-		debug.L2('handler', this.inter(port).handler)
+		debug.L3('handler', this.inter(port).handler)
 		let ihandler = this.inter(port).handler.bind(this)
 		// inside the listener `this` is the interrupt not the chip/bank
-		this.inter(port).on('fired', function () {
+		this.inter(port).on('fired', async function () {
 			debug.L1(`interrupt from ${this.pin_number}`)
-			ihandler(port)
+			let data = await ihandler(port)
+			debug.L2(`port interrupt event 'fired' data => ${data.bank} on port ${data.port} pin# ${data.pin} pid ${data.pid}`)
+			chip.emit('fired', data) // emit up the class chain
 		})
 
 	}
@@ -119,6 +128,7 @@ class MCP23008 extends Device {
 				await this.write(portReg(reg, port), byte)
 			}
 		}
+		debug.L1(`done writing mcp pins config`)
 	} // end writePinsCfg
 
 	async readPort(port, opts = {}) {
@@ -160,7 +170,7 @@ class MCP23008 extends Device {
 		this.ports[port].state.value = byte
 	}
 
-	async on(pins, port, format) {
+	async pinsOn(pins, port, format) {
 		if ('AB'.indexOf(port) === -1) {
 			format = port
 			port = 'A'
@@ -174,7 +184,7 @@ class MCP23008 extends Device {
 		await this.writePort(pins, 'force', port)
 	}
 
-	async off(pins, port, format) {
+	async pinsOff(pins, port, format) {
 		if ('AB'.indexOf(port) === -1) {
 			format = port
 			port = 'A'
diff --git a/test/mcp.test.js b/test/mcp.test.js
index 91a7f35..f79376d 100644
--- a/test/mcp.test.js
+++ b/test/mcp.test.js
@@ -32,10 +32,10 @@ function eachpin() {
 	it('==> test each pin', async function () {
 
 		for (let pin of mcp.ports[PORT].pins) {
-			await mcp.on(pin.address, PORT)
+			await mcp.pinsOn(pin.address, PORT)
 			let result = await mcp.readPort(PORT)
 			expect(result, `pin ${pin.id} at address ${pin.address} write/read failed`).to.equal(pin.address)
-			await mcp.off(pin.address, PORT)
+			await mcp.pinsOff(pin.address, PORT)
 			await pause(MS)
 		}
 	})
@@ -45,14 +45,14 @@ function somepins() {
 	it('==> on, off toggle some pins', async function () {
 
 		let pins = [1, 7, 8]
-		await mcp.on(pins, PORT, 'PLC')
+		await mcp.pinsOn(pins, PORT, 'PLC')
 		let shouldbe = [1, 7, 8]
 		let result = await mcp.readPort(PORT, { format: 'PLC' })
 		expect(result.sort(), 'pin write/read failed on').to.deep.equal(shouldbe.sort())
 		await pause(MS)
 
 		pins = [2, 1, 7]
-		await mcp.on(pins, PORT, 'PLC')
+		await mcp.pinsOn(pins, PORT, 'PLC')
 		shouldbe = [2, 1, 7, 8]
 		result = await mcp.readPort(PORT, { format: 'PLC' })
 		expect(result.sort(), 'pin write/read failed on 2').to.deep.equal(shouldbe.sort())
@@ -66,7 +66,7 @@ function somepins() {
 		await pause(MS)
 
 		pins = [2, 1, 6, 7]
-		await mcp.off(pins, PORT, 'PLC')
+		await mcp.pinsOff(pins, PORT, 'PLC')
 		shouldbe = [8]
 		result = await mcp.readPort(PORT, { format: 'PLC' })
 		expect(result.sort(), 'pin write/read failed off').to.deep.equal(shouldbe.sort())