Fix #20, disableChannel bug() a.o. (#21)

- Fix #20, **disableChannel()** bug + optimize.
- Fix **isConnected(address, channel)** bug.
- update keywords.txt
- update readme.md
- add **uint8_t find(address)** function, returns mask.
- update / add examples.

CHANGELOG.md

@@ -6,11 +6,20 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.3.0] - 2024-04-15
+- Fix #20, **disableChannel()** bug + optimize.
+- Fix **isConnected(address, channel)** bug.
+- update keywords.txt
+- update readme.md
+- add **uint8_t find(address)** function, returns mask.
+- update / add examples.
+
+----
+
 ## [0.2.2] - 2024-01-01
 - add **bool isConnected(uint8_t address, uint8_t channel)**
 - minor edits
 
-
 ## [0.2.1] - 2023-12-09
 - add derived classes
   - PCA9543 (2 channel), PCA9545 (4 channel), PCA9546 (4 channel)

README.md

@@ -99,9 +99,6 @@ There are however small differences, check the data sheets to see the details.
 deviceAddress = 0x70 .. 0x77, wire = Wire or WireN.
 - **bool begin(uint8_t mask = 0x00)**  set mask of channels to be enabled, default all disabled.
 - **bool isConnected()** returns true if address of the multiplexer is found on I2C bus.
-- **bool isConnected(uint8_t address, uint8_t channel)** find address on selected channel.
-Note that this changes the selected and or enabled channels.
-Returns true if found.
 
 The derived classes PCA9548/PCA9546 have the same interface, except constructor.
 (see #15)
@@ -114,9 +111,17 @@ The derived classes PCA9548/PCA9546 have the same interface, except constructor.
 
 #### Find device
 
-- **bool isConnected(uint8_t address)** returns true if arbitrary address is found on I2C bus.
-This can be used to verify if a certain device is available (or not) on an **enabled** channel.
-So it does not scan all 8 channels to see if any of them has a device with the address given.
+- **bool isConnected(uint8_t address)** returns true if arbitrary address is found on the 
+current I2C bus + selected channels.
+This can be used to verify if a certain device is available (or not) on any **enabled** channel.
+So it does not scan all (8) channels to see if any of them has a device with the address given.
+- **bool isConnected(uint8_t address, uint8_t channel)** find address on selected channel.
+Note that this function changes the selected and or enabled channels.
+Returns true if found.
+- **uint8_t find(uint8_t address)** returns a mask with bits set for channels 
+where the address is found. It scans all channels available.
+Note that this function changes the selected and or enabled channels.
+Returns 0 when the address is not found on any channel, or one bit set per channel found.
 
 
 #### Channel functions
@@ -145,17 +150,19 @@ Optional the library can reset the device.
 - **void setResetPin(uint8_t resetPin)** sets the pin to reset the chip.
 - **void reset()** trigger the reset pin.
 
+
 #### Debug
 
-- **int getError()** returns the last I2C error.
+- **int getError()** returns the last (I2C) status / error.
 
 
 #### Forced IO
 
 When forced IO is set, all writes and read, e.g. **uint8_t getChannelMask()**, will go to the device.
 If the **forced-IO** flag is set to false, it will cache the value of the channels enabled.
 This will result in far more responsive and faster calls.
-Note that writes are only optimized if the channels are already set.
+Note that writes are only optimized if the channels are already set.  
+Forced IO is also used to speed up **getChannelMask()**.
 
 - **void setForced(bool forced = false)** set forced write, slower but more robust.
   - forced == false == fast mode (default).
@@ -165,6 +172,8 @@ Note that writes are only optimized if the channels are already set.
 
 #### Interrupts
 
+(not tested)
+
 The PCA9545 and PCA9543 support interrupts. 
 These two derived classes have implemented the
 
@@ -200,6 +209,10 @@ Not implemented yet, preparation for future.
 - set an "always enabled" mask.
   - investigate the consequences!
 - extend the unit tests.
+- **uint8_t find(address)** returns a mask of channel where address is found
+- restore channel in **isConnected(address, channel);
+- add guard in **reset()**, is the pin set?
+
 
 #### Wont
 

TCA9548.cpp

@@ -1,7 +1,7 @@
 //
 //    FILE: TCA9548.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.2.2
+// VERSION: 0.3.0
 //    DATE: 2021-03-16
 // PURPOSE: Arduino Library for TCA9548 I2C multiplexer and compatibles.
 
@@ -45,7 +45,20 @@ bool TCA9548::isConnected(uint8_t address)
 bool TCA9548::isConnected(uint8_t address, uint8_t channel)
 {
   if (!selectChannel(channel)) return false;
-  return isConnected(_address);
+  return isConnected(address);
+}
+
+
+uint8_t TCA9548::find(uint8_t address)
+{
+  uint8_t mask = 0x00;
+  for (uint8_t ch = 0; ch < _channels; ch++)
+  {
+    //  will work partially if MP is off line (by choice).
+    selectChannel(ch);
+    if (isConnected(address)) mask |= (1 << ch);
+  }
+  return mask;
 }
 
 
@@ -58,30 +71,21 @@ uint8_t TCA9548::channelCount()
 bool TCA9548::enableChannel(uint8_t channel)
 {
   if (channel >= _channels) return false;
-  if (!isEnabled(channel))
-  {
-    setChannelMask(_mask | (0x01 << channel));
-  }
-  return true;
+  return setChannelMask(_mask | (0x01 << channel));
 }
 
 
 bool TCA9548::disableChannel(uint8_t channel)
 {
   if (channel >= _channels) return false;
-  if (!isEnabled(channel))
-  {
-    setChannelMask(_mask & ~(0x01 << channel));
-  }
-  return true;
+  return setChannelMask(_mask & ~(0x01 << channel));
 }
 
 
 bool TCA9548::selectChannel(uint8_t channel)
 {
   if (channel >= _channels) return false;
-  setChannelMask(0x01 << channel);
-  return true;
+  return setChannelMask(0x01 << channel);
 }
 
 

TCA9548.h

@@ -2,7 +2,7 @@
 //
 //    FILE: TCA9548.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.2.2
+// VERSION: 0.3.0
 //    DATE: 2021-03-16
 // PURPOSE: Arduino Library for TCA9548 I2C multiplexer and compatibles.
 //     URL: https://github.com/RobTillaart/TCA9548
@@ -12,7 +12,7 @@
 #include "Wire.h"
 
 
-#define TCA9548_LIB_VERSION             (F("0.2.2"))
+#define TCA9548_LIB_VERSION             (F("0.3.0"))
 
 
 //  ERROR CODES (to be elaborated)
@@ -33,6 +33,8 @@ class TCA9548
   bool    isConnected(uint8_t address);       //  find any address on I2C bus
   bool    isConnected(uint8_t address, uint8_t channel);  //  find address on selected channel
 
+  uint8_t find(uint8_t address);  // returns a mask with channels
+
   //  channel = 0..channelCount()-1
   uint8_t channelCount();
   bool    enableChannel(uint8_t channel);     //  enable this channel non exclusive
@@ -61,13 +63,13 @@ class TCA9548
 
 
 protected:
-  uint8_t   _address;
-  TwoWire*  _wire;
-  uint8_t   _mask;             //  caching mask = status of channels
-  uint8_t   _resetPin;         //  default not set == -1 (255)
-  bool      _forced;
-  int       _error;
-  uint8_t   _channels;         //  PCA954x support.
+  uint8_t    _address;
+  TwoWire *  _wire;
+  uint8_t    _mask;             //  caching mask = status of channels
+  uint8_t    _resetPin;         //  default not set == -1 (255)
+  bool       _forced;
+  int        _error;
+  uint8_t    _channels;         //  PCA954x support.
 };
 
 

examples/TCA9548_find/TCA9548_find.ino

@@ -0,0 +1,52 @@
+//
+//    FILE: TCA9548_find.ino
+//  AUTHOR: Rob Tillaart
+// PURPOSE: demo TCA9548 I2C multiplexer
+//     URL: https://github.com/RobTillaart/TCA9548
+
+
+#include "TCA9548.h"
+
+TCA9548 MP(0x70);
+
+uint8_t channels = 0;
+
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+  Serial.print("TCA9548_LIB_VERSION: ");
+  Serial.println(TCA9548_LIB_VERSION);
+  Serial.println();
+
+  Wire.begin();
+  if (MP.begin() == false)
+  {
+    Serial.println("COULD NOT CONNECT TO MULTIPLEXER");
+  }
+
+  channels = MP.channelCount();
+  Serial.print("CHAN:\t");
+  Serial.println(MP.channelCount());
+
+  //  adjust address range to your needs.
+  for (uint8_t addr = 60; addr < 70; addr++)
+  {
+    if (addr % 10 == 0) Serial.println();
+    Serial.print(addr);
+    Serial.print("\t");
+    Serial.print(MP.find(addr), BIN);
+    Serial.println();
+  }
+
+  Serial.println("done...");
+}
+
+
+void loop()
+{
+}
+
+
+//  -- END OF FILE --

examples/tca9548_demo/tca9548_demo.ino

@@ -1,5 +1,5 @@
 //
-//    FILE: tca9548_demo.ino
+//    FILE: TCA9548_demo.ino
 //  AUTHOR: Rob Tillaart
 // PURPOSE: demo TCA9548 I2C multiplexer
 //     URL: https://github.com/RobTillaart/TCA9548

examples/tca9548_search_device/tca9548_search_device.ino

@@ -1,8 +1,10 @@
 //
-//    FILE: tca9548_search_device.ino
+//    FILE: TCA9548_search_device.ino
 //  AUTHOR: Rob Tillaart
 // PURPOSE: demo TCA9548 I2C multiplexer
 //     URL: https://github.com/RobTillaart/TCA9548
+//
+//    NOTE: since 0.3.0 a find function is added.
 
 
 #include "TCA9548.h"
@@ -28,7 +30,7 @@ void setup()
   }
 
   Serial.println("\nScan the channels of the multiplexer for searchAddress.\n");
-  for (int chan = 0; chan < 8; chan++)
+  for (int chan = 0; chan < MP.channelCount(); chan++)
   {
     MP.selectChannel(chan);
     bool b = MP.isConnected(searchAddress);

keywords.txt

@@ -11,7 +11,9 @@ PCA9543	KEYWORD1
 # Methods and Functions (KEYWORD2)
 begin	KEYWORD2
 isConnected	KEYWORD2
+find	KEYWORD2
 
+channelCount	KEYWORD2
 enableChannel	KEYWORD2
 disableChannel	KEYWORD2
 selectChannel	KEYWORD2
@@ -29,6 +31,8 @@ getForced	KEYWORD2
 
 getError	KEYWORD2
 
+
+# Devices with interrupt
 getInterruptMask	KEYWORD2
 
 

library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/TCA9548"
   },
-  "version": "0.2.2",
+  "version": "0.3.0",
   "license": "MIT",
   "frameworks": "*",
   "platforms": "*",

library.properties

@@ -1,5 +1,5 @@
 name=TCA9548
-version=0.2.2
+version=0.3.0
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino Library for TCA9548 I2C multiplexer and compatibles.