MICRO CONTROLLER UNIT INCLUDING AN ERROR INDICATOR MODULE

• US 20160246664A1
• Filed: 05/02/2016
• Published: 08/25/2016
• Est. Priority Date: 07/16/2008
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Pickel, Norbert, Bahr, Axel, Beattie, Derek, Birnie, Andrew, Culshaw, Carl
• Granted Patent: US 10,095,567 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60R 16/023 for transmission of signals between vehicle parts or subsystems
• CPC Class Codes: G06F 11/0721 within a central processing unit [CPU]
• CPC Class Codes: G06F 11/0739 in a data processing system embedded in automotive or aircraft systems
• CPC Class Codes: G06F 11/0757 by exceeding a time limit, i.e. time-out, e.g. watchdogs
• CPC Class Codes: G06F 11/0772 Means for error signaling, e.g. using interrupts, exception flags, dedicated error registers
• CPC Class Codes: G07C 5/085 using electronic data carriers

Abstract

A micro controller unit including an error indicator hardware module, the error indicator module being arranged to respond to event signals representative of internal and external fault and error events perturbing the micro controller unit function by registering in non-volatile memory a record of the nature of each of the events, wherein the record of the events is inaccessible to alteration.

Claims

1. An automotive system comprising:

a programmable microcontroller unit (MCU) configured to execute instructions to implement an automotive electronics control system; and

an error indicator module configured to operate independently from the MCU, the error indicator module comprising;

a non-volatile memory, the non-volatile memory inaccessible by the MCU; and

control logic configured to respond to an event signal representative of the occurrence of an event having a potential to interfere with correct functionality of the MCU by storing in the non-volatile memory a record of the nature of the event.

2. The system of claim 1, wherein the error indicator module is arranged to store the record of the event independently of software executed by the MCU external to the error indicator module.

3. The system of claim 1, wherein the error indicator module is arranged to trigger storing the record of the event on detection of a transition of the event signal.

4. The system of claim 1, wherein the error indicator module is arranged to store in the non-volatile memory a record to indicate the time as well as of the nature of the event.

5. The system of claim 1, wherein the error indicator module is arranged to latch a value representative of the record of the event to be stored, write the latched value to the non-volatile memory at an address, and increment the non-volatile memory address in preparation for a subsequent event signal.

6. The system of claim 1, wherein the error indicator module is further arranged to provide an output command signal to a watchdog MCU as a function of the nature of the event, in response to the event signal.

7. The system of claim 1, wherein the error indicator module further comprises a buffer configured to capture simultaneous or quasi-simultaneous event signals.

8. The system of claim 1, wherein the error indicator module is further arranged to respond to a signal representative of a recovery from the event by storing in the non-volatile memory a record of a recovery from the event.

9. The system of claim 1, wherein the error indicator module further comprises an assert module selectively responsive to the event signal to provide an output command signal as a function of the nature of the event.

10. A method comprising:

receiving an event signal at an error indicator module included at an automotive electronics control system, the event signal representative of an event having a potential to interfere with correct functionality of a programmable microcontroller unit (MCU) included at the automotive electronics control system; and

storing at a non-volatile memory included at the error indicator module a record of the nature of the event, the non-volatile memory inaccessible by the MCU.

11. The method of claim 10, further comprising:

storing the record of the event independently of software executed by the MCU external to the error indicator module.

12. The method of claim 10, further comprising:

triggering the storing the record of the event in response to detection of a transition of the event signal.

13. The method of claim 10, further comprising:

storing at the non-volatile memory a record to indicate the time as well as of the nature of the event.

14. The method of claim 10, further comprising:

latching a value representative of the record of the event to be stored;

writing the latched value at the non-volatile memory at an address; and

incrementing the non-volatile memory address in preparation for a subsequent event signal.

15. The method of claim 10, further comprising:

providing, by the error indicator module, an output command signal to a watchdog MCU as a function of the nature of the event, in response to receiving the event signal.

16. The method of claim 10, further comprising:

buffering event signals received at the error indicator module to provide recording of simultaneous or quasi-simultaneous event signals.

17. The method of claim 10, further comprising:

receiving at the error indicator module a second event signal representative of a recovery from the event; and

storing at the non-volatile memory a record of the recovery from the event.

18. The method of claim 10, further comprising:

providing, by the error indicator module, a command signal to the MCU, the command signal a function of the nature of the event.

19. An error indicator module comprising:

a capture module to receive event signals;

a non-volatile memory, the non-volatile memory inaccessible by the MCU;

control logic configured to respond to a first event signal representative of an event having a potential to interfere with correct functionality of the MCU by storing in the non-volatile memory a record of the nature of the event; and

an assert module selectively responsive to the event signal to provide an output command signal as a function of the nature of the event,

wherein the error indicator module is configured to operate independently from software executed by a programmable microcontroller unit (MCU), the MCU configured to implement an automotive electronics control system.

20. The error indicator module of claim 19, wherein the control logic is arranged to store the record of the event independently of software executed by the MCU external to the error indicator module.