MCP.read(pin) always returns 1

[Obili69]

Hello Thanks for the great library I have a problem when using all read functions with the MCP23S17. I have a switch on a dev board and pull PA 0-2 and PA 0-2 to either VCC(3.3V) or GND. Im using your lib example(digital read). I changed one line. SPI.begin(); to SPI.begin(12, 11, 13, 42); Im using the MIRKOE EXPAND click from mirkoe end an esp32s3 The serial output looks like this

MCP23S17_LIB_VERSION: 0.5.0
true
1
1
HWSPI: 1
TEST read1(pin)
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
TEST read1(pin)
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
TEST read1(pin)

Best and thank you

[RobTillaart]

thanks for reporting this issue, as I am rather busy I have little time to investigate. might take several days

[Obili69]

No problem. Im currently also investigating the issue.

[RobTillaart]

Some questions:

• Have you connected the line 10 to the select line of the MCP23S17?
• if I understand it well it returns 1 even if you connect to GND?
• there is no pull up resistor in your hardware?

[Obili69]

Some answers :)

• im using pin 42 as CS
• Yes i had now im only getting 0 even if high im not sure why it flipped
• No its just a switch that changes from VCC to GND

CODE:

//
//    FILE: MCP23S17_digitalRead.ino
//  AUTHOR: Rob Tillaart
// PURPOSE: test MCP23S17 library
//     URL: https://github.com/RobTillaart/MCP23S17

#include "MCP23S17.h"

MCP23S17 MCP(42);
int rv = 0;

void setup()
{
  Serial.begin(115200);
  Serial.println();
  Serial.print("MCP23S17_LIB_VERSION: ");
  Serial.println(MCP23S17_LIB_VERSION);
  delay(100);

  SPI.begin(12, 11, 13, 42);

  rv = MCP.begin();
  Serial.println(rv ? "true" : "false");

  rv = MCP.pinMode8(0, 0xFF);
  Serial.println(rv);
  rv = MCP.pinMode8(1, 0x00);
  Serial.println(rv);

  Serial.print("HWSPI: ");
  Serial.println(MCP.usesHWSPI());

  Serial.println("TEST read1(pin)");
  for (int pin = 0; pin < 8; pin++)
  {
    int val = MCP.read1(pin);
    Serial.print(val);
    Serial.print(' ');
    delay(100);
  }
  Serial.println();
  MCP.write8(1, 0xFF);
}

void loop()
{
  delay(1000);
  Serial.println("TEST read1(pin)");
  for (int pin = 0; pin < 8; pin++)
  {
    int val = MCP.read1(pin);
    Serial.print(val);
    Serial.print(' ');
    delay(100);
  }
  Serial.println();

}

//  -- END OF FILE --

(added code tags)

[RobTillaart]

Could you run a test with software Spi ? You should be able to use the same pins.

MCP23S17 MCP(select, datain, dataout, clock)

A thought popped up Could it be that datain and dataout were swapped?

[Obili69]

Okay so i tried it with sw SPI. The Outputs are still working no reaction from the inputs. I hooked the Inputs directly to VCC testet the voltage. I have 3.3V on the PIN.

[RobTillaart]

Do you use this one - https://www.mikroe.com/expand-2-click (I2C) or - https://www.mikroe.com/expand-click (SPI)

just to be sure.

[Obili69]

I got the Mirkoe-951 As far as i saw thats the SPI version. What i think is wierd is that the Outputs are working BTW props for the amount of libs you crated

[Obili69]

News I found a second click board and i tried that. It just works now. Thanks A lot anyway. Hope you keep up the great work. I donated you a bit. Sorry for the time waste.

[RobTillaart]

Sorry for the time waste.

If you learn something, time is never wasted! Was it a different type of board, or is the first one a faulty one? just to understand the root cause.

Hope you keep up the great work, I donated you a bit.

Will do so, thank you, much appreciated!

[Obili69]

The board was just faulty only the port i used as a output was working i changed the port i uses as input to output and it didnt work anymore. :( Thanks have a nice day