.travis.yml

@@ -1,6 +1,6 @@
 language: python
 python:
-    - "3.6"
+    - "2.7"
 
 # Cache PlatformIO packages using Travis CI container-based infrastructure
 sudo: false

README.md

@@ -1,6 +1,6 @@
 SPIFlash
 ========
-[![Build Status](https://app.travis-ci.com/LowPowerLab/SPIFlash.svg?branch=master)](https://app.travis-ci.com/LowPowerLab/SPIFlash)
+[![Build Status](https://travis-ci.org/LowPowerLab/SPIFlash.svg?branch=master)](https://travis-ci.org/LowPowerLab/SPIFlash)
 [![GitHub release](https://img.shields.io/github/release/LowPowerLab/SPIFlash.svg)](https://github.com/LowPowerLab/SPIFlash)
 [![GitHub issues](https://img.shields.io/github/issues/LowPowerLab/SPIFlash.svg)](https://github.com/LowPowerLab/SPIFlash/issues)
 [![GitHub pull requests](https://img.shields.io/github/issues-pr/LowPowerLab/SPIFlash.svg)](https://github.com/LowPowerLab/SPIFlash/pulls)

SPIFlash.cpp

@@ -38,13 +38,8 @@ uint8_t SPIFlash::UNIQUEID[8];
 
 /// IMPORTANT: NAND FLASH memory requires erase before write, because
 ///            it can only transition from 1s to 0s and only the erase command can reset all 0s to 1s
-///            See http://en.wikipedia.org/wiki/Flash_memory
-///            The smallest range that can be erased is a sector (4K, 32K, 64K); there is also a chip erase command
-
-/// IMPORTANT: When flash chip is powered down, aka sleeping, the only command it will respond to is 
-///            Release Power-down / Device ID (ABh), per section 8.2.19 of the W25X40CL datasheet.
-///            This means after using the sleep() function of this library, wake() must be the first
-///            function called. If other commands are used, the flash chip will ignore the commands. 
+/// See http://en.wikipedia.org/wiki/Flash_memory
+/// The smallest range that can be erased is a sector (4K, 32K, 64K); there is also a chip erase command
 
 /// Constructor. JedecID is optional but recommended, since this will ensure that the device is present and has a valid response
 /// get this from the datasheet of your flash chip
@@ -185,14 +180,11 @@ void SPIFlash::command(uint8_t cmd, boolean isWrite){
     command(SPIFLASH_WRITEENABLE); // Write Enable
     unselect();
   }
-  //  wait for any write/erase to complete
+  //wait for any write/erase to complete
   //  a time limit cannot really be added here without it being a very large safe limit
   //  that is because some chips can take several seconds to carry out a chip erase or other similar multi block or entire-chip operations
-  //  
-  //  Note: If the MISO line is high, busy() will return true. 
-  //        This can be a problem and cause the code to hang when there is noise/static on MISO data line when:
-  //        1) There is no flash chip connected
-  //        2) The flash chip connected is powered down, aka sleeping. 
+  //  a recommended alternative to such situations where chip can be or not be present is to add a 10k or similar weak pulldown on the
+  //  open drain MISO input which can read noise/static and hence return a non 0 status byte, causing the while() to hang when a flash chip is not present
   if (cmd != SPIFLASH_WAKE) while(busy());
   select();
   SPI.transfer(cmd);
@@ -300,46 +292,11 @@ void SPIFlash::blockErase64K(uint32_t addr) {
   unselect();
 }
 
-/// found() - checks there is a FLASH chip by checking the deviceID repeatedly - should be a consistent value
-uint8_t SPIFlash::found() {
-  uint16_t deviceID=0;
-  wakeup(); //if sleep() was previously called, wakeup() is required or it's non responsive
-  for (uint8_t i=0;i<10;i++) {
-    uint16_t idNow = readDeviceId();
-    if (idNow==0 || idNow==0xffff || (i>0 && idNow != deviceID)) {
-      deviceID=0;
-      break;
-    }
-    deviceID=idNow;
-  }
-  if (deviceID==0) { //NO FLASH CHIP FOUND, ABORTING
-    return false;
-  }
-  return true;
-}
-
-///regionIsEmpty() - check a random flashmem byte array is all clear and can be written to (ie. it's all 0xff)
-uint8_t SPIFlash::regionIsEmpty(uint32_t startAddress, uint8_t length) {
-  uint8_t flashBuf[length];
-  readBytes(startAddress, flashBuf, length);
-  for (uint8_t i=0;i<length;i++) if (flashBuf[i]!=0xff) return false;
-  return true;
-}
-
-/// Put flash memory chip into power down mode
-/// WARNING: after this command, only the WAKEUP and DEVICE_ID commands are recognized
-/// hence a wakeup() command should be invoked first before further operations
-/// If a MCU soft restart is possible with flash chip left in sleep(), then a wakeup() command
-///   should always be invoked before any other commands to ensure the flash chip was not left in sleep
 void SPIFlash::sleep() {
   command(SPIFLASH_SLEEP);
   unselect();
 }
 
-/// Wake flash memory from power down mode
-/// NOTE: this command is required after a sleep() command is used, or no other commands will be recognized
-/// If a MCU soft restart is possible with flash chip left in sleep(), then a wakeup() command
-///   should always be invoked before any other commands to ensure the flash chip was not left in sleep
 void SPIFlash::wakeup() {
   command(SPIFLASH_WAKE);
   unselect();

SPIFlash.h

@@ -105,9 +105,7 @@ public:
   void blockErase64K(uint32_t addr);
   uint16_t readDeviceId();
   uint8_t* readUniqueId();
-  uint8_t found();
-  uint8_t regionIsEmpty(uint32_t startAddress, uint8_t length);
-
+  
   void sleep();
   void wakeup();
   void end();

examples/SPIFlash_Detect/SPIFlash_Detect.ino

@@ -3,30 +3,27 @@
 #include <SPIFlash.h>   //https://github.com/lowpowerlab/spiflash
 #include <SPI.h>
 
-#define SERIAL_BAUD      115200
-#define BLINK_FAST_DELAY 50
-#define BLINK_SLOW_DELAY 1000
+#define SERIAL_ENABLE
+#define BLINK_FAST_DELAY 100
+#define BLINK_SLOW_DELAY 500
 
 SPIFlash flash(SS_FLASHMEM, 0xEF30); //EF40 for 16mbit windbond chip
 int LEDTIME = 500;
 
 // the setup routine runs once when you press reset:
 void setup() {
-#ifdef SERIAL_BAUD
-  Serial.begin(SERIAL_BAUD);
-  while (!Serial) delay(100); //wait until Serial/monitor is opened
+#ifdef SERIAL_ENABLE
+  Serial.begin(115200);
+  delay(4000); //wait a bit until SerialMonitor can be opened
 #endif
   pinMode(LED_BUILTIN, OUTPUT);
 
-  //ensure the radio module CS pin is pulled HIGH or it might interfere!
-  pinMode(SS, OUTPUT); digitalWrite(SS, HIGH);
-
-  //ensure FLASH chip is not sleep mode (unresponsive)
-  flash.wakeup();
   if (flash.initialize()) {
     Serial.println("SPI Flash Init OK!");
     LEDTIME = BLINK_SLOW_DELAY;
-  } else {
+  }
+  else
+  {
     Serial.println("SPI Flash Init FAIL! (is chip soldered?)");
     LEDTIME = BLINK_FAST_DELAY;
   }

examples/SPIFlash_ReadWrite/SPIFlash_ReadWrite.ino

@@ -2,17 +2,14 @@
 // This sketch is an example of using the SPIFlash library with a Moteino
 // that has an onboard SPI Flash chip. This sketch listens to a few serial commands
 // Hence type the following commands to interact with the SPI flash memory array:
-//'c' - read flash chip's deviceID 10 times to ensure chip is present
-//'d' - dump first 256 bytes on the chip
-//'e' - erase entire flash chip
-//'E' - erase last 4K block in flash chip
-//'D' - dump first 256 bytes in the last 4K block
-//'i' - read deviceID
-//'0'-'9' - write 0xaa/0xbb bytes at addresses 0..9, 520192..520447
+// - 'd' dumps the first 256bytes of the flash chip to screen
+// - 'e' erases the entire memory chip
+// - 'i' print manufacturer/device ID
+// - [0-9] writes a random byte to addresses [0-9] (either 0xAA or 0xBB)
 // Get the SPIFlash library from here: https://github.com/LowPowerLab/SPIFlash
 // Note: if other SPI devices are present, ensure their CS pins are pulled up or set HIGH
 // **********************************************************************************
-// (C) 2021 Felix Rusu, LowPowerLab.com
+// (C) 2020 Felix Rusu, LowPowerLab.com
 // Library and code by Felix Rusu - felix@lowpowerlab.com
 // **********************************************************************************
 // License
@@ -56,17 +53,9 @@ uint16_t expectedDeviceID=0xEF30;
 SPIFlash flash(SS_FLASHMEM, expectedDeviceID);
 
 void setup(){
-#ifdef SERIAL_BAUD
   Serial.begin(SERIAL_BAUD);
-  while (!Serial) delay(100); //wait until Serial/monitor is opened
-#endif
-  pinMode(LED_BUILTIN, OUTPUT);
-
   Serial.print("Start...");
 
-  //ensure the radio module CS pin is pulled HIGH or it might interfere!
-  pinMode(SS, OUTPUT); digitalWrite(SS, HIGH);
-
   if (flash.initialize())
   {
     Serial.println("Init OK!");
@@ -84,10 +73,7 @@ void setup(){
   Serial.println("'c' - read flash chip's deviceID 10 times to ensure chip is present");
   Serial.println("'d' - dump first 256 bytes on the chip");
   Serial.println("'e' - erase entire flash chip");
-  Serial.println("'E' - erase last 4K block in flash chip");
-  Serial.println("'D' - dump first 256 bytes in the last 4K block");
   Serial.println("'i' - read deviceID");
-  Serial.println("'0'-'9' - write 0xaa/0xbb bytes at addresses 0..9, 520192..520447");
   Serial.println("************************\n");
   delay(1000);
 }
@@ -97,26 +83,16 @@ void loop(){
   // ie: display first 256 bytes in FLASH, erase chip, write bytes at first 10 positions, etc
   if (Serial.available() > 0) {
     input = Serial.read();
-    if (input == 'd') { //d=dump flash area
-      Serial.println("Flash content (256 bytes, starting address 0):");
+    if (input == 'd') //d=dump flash area
+    {
+      Serial.println("Flash content:");
       int counter = 0;
 
-      while(counter<256){
-        Serial.print(flash.readByte(counter), HEX);
-        counter++;
-        if (counter%16 == 0) Serial.println(); else Serial.print('.');
-      }
-      Serial.println();
-    }
-    else if (input == 'D') { //d=dump flash area @ last 4K block
-      Serial.println("Flash content (256bytes, starting address 520192):");
-      uint32_t counter = 520192;
-
-      while(counter<520192+256){
-        Serial.print(flash.readByte(counter), HEX);
-        counter++;
-        if (counter%16 == 0) Serial.println(); else Serial.print('.');
+      while(counter<=256){
+        Serial.print(flash.readByte(counter++), HEX);
+        Serial.print('.');
       }
+      
       Serial.println();
     }
     else if (input == 'c') {
@@ -142,13 +118,6 @@ void loop(){
       while(flash.busy());
       Serial.println("DONE");
     }
-    else if (input == 'E')
-    {
-      Serial.print("Erasing last 4K block @520192 ... ");
-      flash.blockErase4K(520192);
-      while(flash.busy());
-      Serial.println("DONE");
-    }
     else if (input == 'i')
     {
       Serial.print("DeviceID: ");
@@ -158,19 +127,21 @@ void loop(){
     {
       Serial.print("\nWriteByte("); Serial.print(input); Serial.print(")");
       flash.writeByte(input-48, millis()%2 ? 0xaa : 0xbb);
-      flash.writeByte(input-48+520192, millis()%2 ? 0xaa : 0xbb);
     }
   }
 
   // Periodically blink the onboard LED while listening for serial commands
-  if ((int)(millis()/500) > lastPeriod) {
+  if ((int)(millis()/500) > lastPeriod)
+  {
     lastPeriod++;
+    pinMode(LED_BUILTIN, OUTPUT);
     digitalWrite(LED_BUILTIN, lastPeriod%2);
   }
 }
 
 void Blink(int DELAY_MS, byte loops)
 {
+  pinMode(LED_BUILTIN, OUTPUT);
   while (loops--)
   {
     digitalWrite(LED_BUILTIN,HIGH);