Operating a FIFO memory

• US 9,767,034 B2
• Filed: 05/11/2015
• Issued: 09/19/2017
• 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: Daga, Jean-Michel, Deschildre, Alexandre
• Primary Examiner(s): BATAILLE, PIERRE MICHE
• Application Number:
  US14/708,787
• Publication Number:
  US 20150331805A1
• Time in Patent Office: 862 Days
• Field of Search: 711133, 711159
• 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 (FIFO) memory arranged to store measurement data samples measured by a plurality of data measurement sensors, in which memory an oldest measurement data sample is arranged to be read first, the method comprising:

sampling first measurement data samples from a first measurement sensor of a first type at a first sampling rate and second measurement samples from a second measurement sensor of a second type at a second sampling rate different from the first sampling rate;

storing the first measurement data samples in the FIFO memory

in association with a first tag that identifies the first data measurement sensor based on the sampling of the first measurement data samples at the first sampling rate; and

storing the second measurement data samples in the FIFO memory in association with a second tag that identifies the second data measurement samples based on the sampling of the second measurement data samples at the second sampling rate.

2. The method according to claim 1, further comprising:

receiving the first tag from the first measurement sensor; and

receiving the second tag from the second measurement sensor.

3. The method according to claim 1, wherein the storing the storing the first measurement data samples and storing the second measurement data samples comprise successively storing the first measurement data samples and the second measurement data samples as the first measurement data samples are sampled at the first sampling rate and the second measurement data samples are sampled at the second sampling rate.

4. The method according to claim 1, further comprising:

storing a write location in the FIFO memory at which a next sampled measurement data sample should be stored, by a write pointer; and

storing a read location in the FIFO memory at which a measurement data sample should be read, by a read pointer.

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

6. The method according to claim 5, wherein the flag indicates at least one of:

the FIFO memory is full;

the FIFO memory is empty;

all measurement data samples have been read from the FIFO memory; and

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

7. The method according to claim 1, further comprising outputting at least one measurement data sample from among the first measurement data samples and the second measurement data samples stored in the FIFO memory and a tag associated with the at least one measurement data sample stored in the FIFO memory to a read-out buffer.

8. A first-in first-out memory (FIFO) arranged to store measurement data samples measured by a plurality of data measurement sensors, in which an oldest measurement data sample is arranged to be read first from the FIFO memory, the FIFO memory comprising:

first registers configured to store first measurement data samples in the FIFO memory in association with a first tag that identifies the first data measurement sensor; and

second registers configured to store second measurement data samples in the FIFO memory in association with a second tag that identifies the second measurement samples,

wherein the FIFO memory is configured to receive the first measurement data sampled from a first measurement sensor of a first type at a first sampling rate the second measurement samples from a second measurement sensor of a second type at a second sampling rate different from the first sampling rate and store the first measurement data samples in the first registers in association with the first tag based on the sampling of the first measurement data samples at the first sampling rate and store the second measurement data samples in the second registers in association with the second tag based on the sampling of the second measurement data samples at the second sampling rate.

9. An electronic circuit comprising:

a controller configured to sample first measurement data samples from a first measurement sensor of a first type at a first sampling rate and second measurement samples from a second measurement sensor of a second type at a second sampling rate different from the first sampling rate; and

a first-in first-out memory (FIFO) arranged to store measurement data samples measured by a plurality of data measurement sensors, in which an oldest measurement data sample is arranged to he read first from the FIFO memory, the FIFO memory comprising;

first registers configured to store the first measurement data samples in the FIFO memory in association with a first tag that identifies the first data measurement sensor; and

second registers configured to store the second measurement data samples in the FIFO memory in association with a second tag that identifies the second data measurement samples,

wherein the controller is configured to store the first measurement data samples in the first registers in association with the first tag based on the sampling of the first measurement data samples at the first sampling rate and store the second measurement data samples in the second registers in association with the second tag based on the sampling of the second measurement data samples at the second sampling rate.

10. The electronic circuit according to claim 9, wherein the controller is further configured to determine that the first measurement data samples are sampled from the first measurement sensor and the second measurement data samples are sampled from the second measurement sensor.

11. The electronic circuit according to claim 9, further comprising:

a read-out buffer connected to the memory; and

a master unit connected to the read-out buffer,

wherein the FIFO memory is arranged to automatically send at least an oldest measurement data sample and an associated tag 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 a previous measurement data sample in the read-out buffer.

12. The electronic circuit according to claim 11, wherein the FIFO memory is further configured to send memory status information to the read-out buffer.

13. A non-transitory computer-readable recording medium having recorded thereon a computer program product comprising instructions for implementing a method of operating first-in first-out (FIFO) memory arranged to store measurement data samples measured by a plurality of data measurement sensors, in which memory an oldest measurement data sample is arranged to be read first, the method comprising;

sampling first measurement data samples from a first measurement sensor of a first type at a first sampling rate and second measurement samples from a second measurement sensor of a second type at a second sampling rate different from the first sampling rate;

storing the first measurement data samples in the FIFO memory in association with a first tag that identifies the first data measurement sensor based on the sampling of the first measurement data samples at the first sampling rate; and

storing the second measurement data samples in the FIFO memory in association with a second tag that identifies the second data measurement sample based on the sampling of the second measurement data samples at the second sampling rate.