Inteference between CC3000 WIFI Shield and LCD

Projects Networking, Protocols, and Devices
1

Hardware
Arduino UNO with CC3000 WIFI shield...

... the one which plugs directly into the UNO. The LCD is a standard 16 pin LCD running on a shift register 74HC595 (as shown here in this tutorial Arduino Playground - LiquidCrystal Library).

Pins used
The LCD is using pins 11 and 13 along with a latch pin of A5. The WIFI shield is not modified and I don't see how that would be possible anyway.

Library

Issue
Random inference between the WIFI board and the LCD causing corruption of the LCD text. I'm a newb at this but after reading into it, I believe the issue is related to the fact that both the LCD and the CC3000 both utilise the bus with channels 11 (MOSI I think) and 13 (SPI). Is there anyway for a beginner to get these 2 devices to play nicely? As I can't easily modify the WIFI shield, is there a way to modify the LCD somehow so that it doesn't need to use these pins or get them to share the bus as they should?

Please help!

2

This particular issue turned out to be an error with my wire mapping. This is compatible!

3

I'm working with the same components. Did you resolve it? Did you replace either WiFi shield or LCD shield?

4

Here the sample code I'm using:

#include <LiquidCrystal.h>
#include <Adafruit_CC3000.h>
#include <ccspi.h>
#include <SPI.h>
#include <string.h>
#include "utility/debug.h"

// These are the interrupt and control pins
#define ADAFRUIT_CC3000_IRQ 3 // MUST be an interrupt pin!
// These can be any two pins
#define ADAFRUIT_CC3000_VBAT 5
#define ADAFRUIT_CC3000_CS 10
// Use hardware SPI for the remaining pins
// On an UNO, SCK = 13, MISO = 12, and MOSI = 11
Adafruit_CC3000 cc3000 = Adafruit_CC3000(ADAFRUIT_CC3000_CS, ADAFRUIT_CC3000_IRQ, ADAFRUIT_CC3000_VBAT, SPI_CLOCK_DIVIDER); // you can change this clock speed

#define WLAN_SSID "[redacted]" // cannot be longer than 32 characters!
#define WLAN_PASS "[redacted]"
// Security can be WLAN_SEC_UNSEC, WLAN_SEC_WEP, WLAN_SEC_WPA or WLAN_SEC_WPA2
#define WLAN_SECURITY WLAN_SEC_WPA2

#define IDLE_TIMEOUT_MS 3000 // Amount of time to wait (in milliseconds) with no data
// received before closing the connection. If you know the server
// you're accessing is quick to respond, you can reduce this value.

// What page to grab!
#define WEBSITE "www.adafruit.com"
#define WEBPAGE "/testwifi/index.html"

LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
int readkey;

uint32_t ip;

void setup(void)
{
lcd.begin(16,2);
lcd.clear();
lcd.print("Hello, CC3000!");
lcd.setCursor(0, 1);
lcd.print("Free RAM: "); lcd.print(getFreeRam(), DEC);
delay(1000);
/* Initialise the module */
lcd.setCursor(0, 1);
lcd.print("Initializing...");
if (!cc3000.begin())
{
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Error");
//Serial.println(F("Couldn't begin()! Check your wiring?"));
while(1);
}

// Optional SSID scan
// listSSIDResults();
lcd.setCursor(0, 0);
lcd.print("Connecting to ");
lcd.setCursor(0, 1);
lcd.print(WLAN_SSID);
if (!cc3000.connectToAP(WLAN_SSID, WLAN_PASS, WLAN_SECURITY)) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Failed!");
while(1);
}

lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Connected!");
}

void loop(void)
{
delay(1000);
}