add chris's doc on ESP8266 SPI wiring

Author: phoddie

documentation/devices/esp8266/spidisplaywiring.md

@@ -0,0 +1,44 @@
+# Connecting a SPI display to ESP8266
+
+####Copyright 2017 Moddable Tech, Inc.
+
+####Revised: October 12, 2017
+
+
+
+## Overview
+
+Many Moddable examples include screen and touch UI. These demos have been developed with inexpensive resistive SPI touch displays readily available on eBay and other sources. The displays are 240 x 320 resolution and come in 2.4" and 2.8" sizes. 
+
+Any SPI based screen should work. We have brought up samples and products on many screens including LCD, OLED, eInk. There are a number of display and touch drivers in the Moddable SDK repository. See: modules/drivers/
+
+These inexpensive red resistive displays use the ILI9341 display IC/driver and the XPT2046 IC/driver.
+
+![](./../../assets/moddable_zero/spi-touch-display.jpg)
+
+## Wiring
+
+When wired to an ESP8266 development board as shown below any of the Moddable examples with screen UI will utilize the screen. 
+
+| ILI9341 Display | ESP8266 | Devboard label
+| --- | --- | --- |
+| SDO / MISO | GPIO 12 | (D6) 
+| LED | 3.3V | 
+| SCK | GPIO 14 | (D5) 
+| SDI / MOSI | GPIO 13 | (D7) 
+| DC | GPIO 2 | (D4) 
+| RESET | 3.3V | 
+| GND | GND | 
+| VCC | 3.3V | 
+| T_DO | GPIO 12 | (D6) 
+| T_DIn | GPIO 13 | (D7) 
+| T_CLK | GPIO 14 | (D5) 
+| T_IRQ | GPIO 16 | (D0)
+| T_CS | GPIO 0 | (D3) 
+
+<br>
+<br>
+
+![](./../../assets/moddable_zero/esp-display-wiring.png)
+
+![](./../../assets/moddable_zero/esp-breadboard-display.png)