Fix ESP8266/ESP32 "ISR not in IRAM" runtime exception

[Yveaux]

Refer to: https://forum.mysensors.org/topic/10581/isr-not-in-iram-error

ESP interrupt handlers shall be prefixed with "ICACHE_RAM_ATTR"

[mfalkvidd]

Since this attribute was not required in earlier board versions, maybe we need to check if adding the attribute will break things for older board versions.

[mfalkvidd]

The incompatible change in the esp8266 board definition was introduced in v2.5.1, so a workaround is to use board version 2.5.0 or earlier.

Reference: esp8266/Arduino#6141

[mfalkvidd]

Also see https://groups.google.com/a/arduino.cc/forum/m/#!topic/developers/56VPC9t2MPc which discusses how to generalize the ICACHE_RAM_ATTR requirement. It mentions thatt all functions called from within an ISR also needs the attribute. If that is true, a lot of funcrions will be affected.

[sp9auv]

Problem with ISR not IRAM in a WEMOS or ARDUION is that memory for that handle ISR interrupt must be reserved in a section DECLARATION for values in this way for example
void ICACHE_RAM_ATTR ServiceLimitSwitchUpperShield_12_D6();
// There are solved for ATTACHINTERRUPT - you must declare this before function SETUP (very important )
In a section SETUP you can define
attachInterrupt(digitalPinToInterrupt(12), ServiceLimitSwitchUpperShield_12_D6 , FALLING );

The method ServiceLimitSwitchUpperShield_12_D6 define for example
[[ichache_IRAM_ATTR]]
void ServiceLimitSwitchUpperShield_12_D6()

Take attention what memory is need for your souce code . This value give compilator.With abouve 32 KB may also occur problem . Choice MMU from Tools
as 32 KB cache + 32 KB IRAM (balanced ). You can try other option
de sp9auv