CN104408212A - Data acquisition method for portable data acquisition card - Google Patents

Abstract

The invention discloses a data acquisition method for a portable data acquisition card. The data acquisition method for the portable data acquisition card includes the following steps: S1, starting the power supply of the acquisition card, the data acquisition card samples the AD on the analog signal; S2, after DDR2 caches the sampling data of the 1S, stopping sampling; S3, MCU sends the start data transmission instruction to the FPGA; S4, the FPGA receives the start data transmission instruction and reads the data from DDR2, writes the data to SlaveFIFO through the GPI; S5, MCU detects the data and writes the data to DMA of USB through the GPIF socket; S6, USB reads the data of the DMA buffer area and transmits the data to the external of acquisition card. The method can display the transmission data on time domain and frequency domain, clear the cache timely and guarantee data transmission smooth.

Description

A kind of portable data acquisition card collecting method

Technical field

The present invention relates to a kind of collecting method, particularly a kind of portable data acquisition card collecting method.

Background technology

Data acquisition refers to automatic collection electricity or electric quantity signal from the analog-and digital-unit under tests such as sensor and other Devices to test, delivers in host computer and analyzes, process.Data acquisition system (DAS) is that the measurement software and hardware product combined based on computing machine or other dedicated testing platforms realizes flexibly, user-defined measuring system.Data collecting card, namely realizes the computer extender card of data acquisition function, can pass through USB, 485,232, Ethernet, the bus such as various wireless networks access personal computer.

Data collecting card is used for gathering various types of data, and along with modern comfort is towards digitizing, informationalized high speed development, data acquisition is stuck in every field and obtains applying more and more widely.

Summary of the invention

The object of the invention is to overcome the deficiencies in the prior art, a kind of portable data acquisition card collecting method is provided, the data that the method gathers are after the real-time buffer memory of capture card, capture card outside is transferred to by USB interface, buffer memory can be emptied in time simultaneously, ensure that data acquisition and the smooth and easy of transmission carry out.

The object of the invention is to be achieved through the following technical solutions: a kind of portable data acquisition card collecting method, it comprises the steps:

S1: capture card electric power starting, data collecting card starts to carry out AD sampling to simulating signal;

After the sampled data of S2:DDR2 buffer memory 1S, stop sampling;

S3:MCU sends and starts data transfer instruction to FPGA;

S4:FPGA receives and starts data transfer instruction, reads data, and write data to SlaveFIFO by GPIF from DDR2;

After S5:MCU detects data, write data by GPIF socket to the DMA of USB;

Capture card outside is transferred to after the data of S6:USB reading DMA buffer zone.

It also comprises USB socket and empties buffer area and transmitted data and the step notifying GPIF.

The invention has the beneficial effects as follows: the invention provides a kind of portable data acquisition card collecting method, the data that the method gathers are after the real-time buffer memory of capture card, be transferred to capture card outside by USB interface, buffer memory can be emptied in time simultaneously, ensure that data acquisition and the smooth and easy of transmission carry out.

Accompanying drawing explanation

Fig. 1 is collecting method block diagram;

Fig. 2 is data collecting card structural drawing.

Embodiment

Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail, but protection scope of the present invention is not limited to the following stated.

As shown in Figure 1, a kind of portable data acquisition card collecting method, it comprises the steps:

S1: capture card electric power starting, data collecting card starts to carry out AD sampling to simulating signal;

After the sampled data of S2:DDR2 buffer memory 1S, stop sampling;

S3:MCU sends and starts data transfer instruction to FPGA;

S4:FPGA receives and starts data transfer instruction, reads data, and write data to SlaveFIFO by GPIF from DDR2;

After S5:MCU detects data, write data by GPIF socket to the DMA of USB;

Capture card outside is transferred to after the data of S6:USB reading DMA buffer zone.

It also comprises USB socket and empties buffer area and transmitted data and the step notifying GPIF.

Data collecting card comprises AD converter, FPGA, Clock management chip, DDR2 and MCU, the data collected are transferred to FPGA by described AD converter, FPGA by data buffer storage in DDR2, after the sampled data of buffer memory 1S, the data of collection are transferred to MCU according to the instruction of MCU by FPGA, MCU transfers data in the DMA of USB, transfers data to host computer by USB.The data that 4 road AD of data collecting card sample are cached in capture card 4 DDR2 respectively, after the data of buffer memory 1S, stop sampling.MCU send start to transmit data instruction to FPGA, the data of buffer memory are write data to SlaveFIFO by GPIF after receiving instruction by FPGA again, after MCU detects data, write data by GPIF socket to the DMA of USB, after the data of USB reading DMA buffer zone, be transferred to capture card outside.

Portable data acquisition card collecting method simple and fast of the present invention, can be configured sampling clock by host computer, can select interior external clock and configuration sampling rate; Enter data transfer phase and can select data transmission channel according to demand, the data of DAM buffer zone can be removed simultaneously in time.

Claims (2)

1. a portable data acquisition card collecting method, is characterized in that: it comprises the steps:

S1: capture card electric power starting, data collecting card starts to carry out AD sampling to simulating signal;

After the sampled data of S2:DDR2 buffer memory 1S, stop sampling;

S3:MCU sends and starts data transfer instruction to FPGA;

S4:FPGA receives and starts data transfer instruction, reads data, and write data to SlaveFIFO by GPIF from DDR2;

After S5:MCU detects data, write data by GPIF socket to the DMA of USB;

Capture card outside is transferred to after the data of S6:USB reading DMA buffer zone.

2. a kind of portable data acquisition card collecting method according to claim 1, is characterized in that: it also comprises USB socket and empties buffer area and transmitted data and the step notifying GPIF.