OPERATING A FIFO MEMORY

• US 20150331805A1
• Filed: 05/11/2015
• Published: 11/19/2015
• Est. Priority Date: 05/16/2014
• Status: Active Grant

• Current Assignee: EM Microelectronic - Marin SA (The Swatch Group AG)
• Original Assignee: EM Microelectronic - Marin SA (The Swatch Group AG)
• Inventors: DESCHILDRE, Alexandre, DAGA, Jean-Michel
• Granted Patent: US 9,767,034 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 12/0891 using clearing, invalidating or resetting means
• CPC Class Codes: G06F 2212/1028 Power efficiency
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/45 Caching of specific data in cache memory
• CPC Class Codes: G06F 5/06 for changing the speed of data flow, i.e. speed regularising or timing, e.g. delay lines, FIFO buffers; over- or underrun control therefor G06F7/78 takes precedence
• CPC Class Codes: G06F 5/12 Means for monitoring the fill level; Means for resolving contention, i.e. conflicts between simultaneous enqueue and dequeue operations

Abstract

The present invention concerns a method of operating a first-in first-out memory (9) arranged to store measurement data samples measured by a plurality of data measurement sensors (1, 3, 5), which can operate at various sampling rates. The oldest measurement data sample in the memory (9) is arranged to be read first before the newer measurement data samples. The method comprises: receiving measurement data samples from at least two data measurement sensors (1, 3, 5); and saving the received measurement data samples in the memory (9). Each of the measurement data samples saved in the memory is associated with a tag which is also saved in the memory (9) and which identifies the data measurement sensor (1, 3, 5) which measured the respective measurement data sample.

Claims

1. A method of operating a first-in first-out memory arranged to store measurement data samples measured by a plurality of data measurement sensors, in which memory the oldest measurement data sample is arranged to be read first, the method comprising:

receiving measurement data samples from at least two data measurement sensors of different type; and

saving the received measurement data samples in the memory,

wherein each of the measurement data samples saved in the memory is associated with a tag, also saved in the memory, identifying the data measurement sensor which measured the respective measurement data sample.

2. The method according to claim 1, further comprising, before saving each received measurement data sample, receiving information associated with the respective measurement data sample, wherein the received information identifies the data measurement sensor which measured the respective measurement data sample to be saved.

3. The method according to claim 1, wherein the measurement data samples are received successively.

4. The method according to claim 1, wherein every measurement data sample measured at a given time instant is saved in the memory only once.

5. The method according to claim 1 further comprising:

indicating a write location in the memory, where a next measurement data sample should be saved, by a write pointer; and

indicating the read location in the memory, where the measurement data sample should be read, by a read pointer.

6. The method according to claim 1 further comprising indicating the status of the memory by a flag.

7. The method according to claim 6, wherein the flag is arranged to indicate at least one of the following:

the memory is full;

the memory is empty;

all the measurement data samples have been read; and

the filling of the memory space of the memory has exceeded a given threshold.

8. The method according to claim 1, wherein the method further comprises sending at least the measurement data sample and the associated tag to a read-out buffer.

9. The method according to claim 1, wherein a first one of the measurement sensors is sampled at a first sampling rate and a second measurement sensor is sampled at a second sampling rate, different from the first sampling rate.

10. A computer program product comprising instructions for implementing the steps of a method according to claim 1 when loaded and run on a micro-controller unit for operating the memory.

11. A first-in first-out memory arranged to store measurement data samples measured by a plurality of data measurement sensors, wherein the oldest measurement data sample is arranged to be read first from the memory, the memory comprising means for:

receiving measurement data samples from at least two data measurement sensors of different type; and

saving each of the received measurement data samples in the memory,

wherein the memory comprises means for associating said each measurement data sample with a tag identifying the data measurement sensor which measured the respective measurement data sample, and wherein it comprises means for saving the tag in the memory.

12. An electronic circuit comprising the memory of claim 11 and further comprising the said measurement sensors connected to a control unit connected to the memory, wherein the control unit is arranged to sample measurement data from the measurement sensors by applying different sampling rates for measurements from different measurement sensors.

13. The electronic circuit according to claim 12, wherein the control unit is arranged to determine the measurement sensor from which the measurement data were received.

14. The electronic circuit according to claim 12 further comprising:

a read-out buffer connected to the memory, and

a master unit connected to the read-out buffer,

wherein the memory is arranged to send automatically at least the oldest measurement data sample, and the associated tag in its memory, to the read-out buffer to be read by the master unit, such that each successive measurement data sample arriving in the read-out buffer overwrites the previous measurement data sample in the read-out buffer.

15. The electronic circuit according to claim 14, wherein the memory is further arranged to send memory status information to the read-out buffer.