Multiple MCP23017 - Interrupt Handling (Mode 2)

[augea]

Hello,
I'm going to use multiple MCP23017 as input in a project. Every MCP23017 provides two interrupt ports INTA and INTB. I'm aware that these ports can be connected to an ESP port.
MCP23017 INT-ports can be programmed for interrupts on low active, high active and open drain.
I don't what the driver does.
My idea is to connect all INT-ports of all MSP to one ESP Port.
With open drain configuration of the MSP INT-ports this will work and I could also power the MCP with 5V while the interrupt can be used with 3,3V (pullup to 3,3V).
My question is:
Is the driver in Tasmota using the interrupts pins of MSP23017 in open drain mode?
In my opinion the would always require a pull-up resistor or is the ESP input configured with a weak pull-up in the ESP.
Can I use multiple MSP23017 interrupts by connection them all together?
Do I have to use an external pull-up or is the ESP configured with an internal pullup?
Thank you für your answers.
Karsten

[arendst]

Tasmota supports indiviual chip mirrored INT GPIO's with interrupt on change only.

IOCON is configured like MCP23xWrite(MCP23X17_IOCONA, 0b01011000); // Enable INT mirror, Slew rate disabled, HAEN pins for addressing so ODR = 0 = No open drain and INTPOL = 0 = Active-low. The indiviual chip INT GPIO is configured as INPUT_PULLUP.

I suggest you try without interrupts first and rely on the polling of Tasmota and see how that works.

[arendst]

While looking over the MCP23x config possibilities I see an opportunity to make Open Drain interrupts user configurable.

I'll work on that now.

[arendst]

In latest dev (v14.4.0.1) the following addition has been made:

Template option IOCON - Optional. IOCON I/O Expander configuration register (bitmap: 0 MIRROR 0 DISSLW HAEN ODR INTPOL 0. Default 0b01011000 = 0x58)

Example:

 * Buttons and relays with open-drain INT    B1 B2 B3 B4 B5 B6 B7 B8 R1  R2  R3  R4  R5  R6  R7  R8
 * {"NAME":"MCP23017 A=B1-8, B=R1-8","GPIO":[32,33,34,35,36,37,38,39,224,225,226,227,228,229,230,231],"IOCON":0x5C}

Notice the addition of value pair IOCON 0x5C.

On restart the value becomes active:

00:00:00.078-028 I2C: Bus1 using GPIO05(SCL) and GPIO04(SDA)
00:00:00.086-028 I2C: MCP23017 found at 0x20
00:00:00.089-028 I2C: MCP23017 found at 0x21
00:00:00.095-028 MCP: IOCON 0x5C, Base 0, Template 'MCP23017 A=Ri1-8, B=Ri9-16, C=Ri17-24, D=Ri25-32'

[augea]

Thank you for your quick support.
I will design my schematic with open drain INT ports in case it will work as expected. Since my project is very complex (conservatory control with external sensors and 16 shutter groups and 16 up/down buttons) I will be able to test this after may board is produced in China and soldered by myself.