ZIOL2201 datasheet(44/92 Pages) RENESAS

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ZIOL2xxx Datasheet

April 26, 2016

3.3.10. Interrupt and IC Lock Mode Control

3.3.10.1. Interrupt Handling

The INT_L pin provides indication functionality for a set of IC-internal exceptions. Once an exception had

occurred, expressed as logic low of the INT_L signal, the actual cause can be evaluated by reading the IC’s

status register via the SPI interface. Depending on the condition – a reset of the exception by reading the

corresponding status register can be performed.

The following exceptions are combined in the INT indication functionality:

• Lock caused by power fail detector (refer to chapter 3.5)

• Lock caused by COM-Overload (refer to chapter 3.3.10)

• Lock caused by AUX-Overload (refer to chapter 3.3.10)

• Lock caused by over-temperature (refer to chapter 3.3.10)

• EEPROM-single-bit-error (refer to chapter 3.3.7)

• EEPROM-2bit-error (refer to chapter 3.3.7)

• Valid-flag-cleared due to possibly corrupt EEPROM (refer to chapter 3.3.7)

• WURQ detected (refer to chapter 3.3.4)

Figure 3.14 illustrates the handling of the above mentioned exceptions and their monitoring. It also shows how to

configure the interrupt (INT_L pin) and wake-up (WURQ_L pin) signal generation. Besides several exceptions

concerning channel overload, die over-temperature and IO-Link specific wake-up situations the IC can also signal

problems as regards the EEPROM.

Since the configuration registers get their content initially from the EEPROM, the data should be correct. The

following described features make sure that no corrupt EEPROM data can cause unwanted IC configurations.

An EEPROM single bit error indicates a one bit problem in the content of the EEPROM. Since the EEPROM

includes a self correction, one bit errors will be detected and corrected automatically. However, the indication shall

trigger a rewrite

1 of the entire EEPROM content.

The EEPROM 2-bit error indicates a two bit problem in the content of the EEPROM. That error is not

automatically corrected, so the content of the EEPROM can not be considered as correct. Thus a reprogramming

is absolutely required.

The valid-flag is used to indicate that the last write access to the EEPROM was successful. If the valid-flag

indicates a problem, then the chip configuration has to be regarded as faulty – no save IC function can be

guaranteed. Rewriting of the entire EEPROM content is necessary. In case of a regular write process to the

EEPROM is not completed, for instance by an interruption of the IC supply power within the ongoing write

process, the valid-flag will indicate this as a problem because of the EEPROM content might be corrupt.

Besides the signalization of IC-internal exceptions the IN_L pin signals also the system reset state. The system

reset state is indicated with active low on the INT_L pin.

1 Note: IC versions ZIOL2xx2 do not allow any write access.

ZIOL2201 Datasheet(PDF) 44 Page - Renesas Technology Corp