Self-adaptive 429 data receiving rate receiving method and system based on FPGA

Abstract

The invention provides a self-adaptive 429 data receiving rate receiving method based on an FPGA. The method comprises the steps of S1, performing burr filtering on received 429 +end and -end data; S2, starting timing when only the data with the high level at one end of the +end and the -end exists, caching the received data, ending the timing and ending the caching when the +end or the -end jumps, and obtaining timing t1 and the data received within the time period of the timing t1; S3, starting timing when the data receiving +end or -end jumps from a high level to a low level, and stopping timing until the +end or -end jumps from the low level to the high level to obtain a timing t2; S4, adding the timing t1 and the timing t2 to obtain time t3 required for receiving one bit of 429 data;S5, extracting data with the length of t3 from the cached data to obtain one-bit 429 data; and S6, repeating the steps S1-S5 for 32 times to obtain complete 429 data. According to the invention, the 429 data sending rate of the sending device can be ensured to be changed, and the 429 data can be correctly received in a self-adaptive manner.

Description

technical field [0001] The present invention relates to the communication field, in particular to an FPGA-based receiving method and system for adaptive 429 data receiving rate. Background technique [0002] The ARINC 429 bus protocol was proposed by the American Aviation Electronics Engineering Council (AEC for short) in July 1977 and was approved for use. Protocol standards specify the data information transmission requirements between avionics equipment and related systems. ARINC429 bus has simple structure, stable performance, strong anti-interference and high reliability. It adopts the modulation method of bipolar return-to-zero tri-state code, and the bit rate of the high-speed working rate is 100Kb / s (see figure 1 , each data bit lasts 10us), the bit rate of the low-speed working rate is 12.5Kb / s (12Kb / s~14.5Kb / s) (see figure 2 , each data bit lasts 80us), and its error range is within 1% of the bit rate of the selected content. [0003] The transmission method o...

AI Technical Summary

Problems solved by technology

[0005] 1) The sending rate of the sending device is not standard; the sending rate of the sending device is not standard (the standard sending rate is 100Kb / s or 12.5Kb / s), which may cause the received 429 data error;

[0006] 2) Aging of crystal oscillator: With the prolongation of use time, the sending device has crystal aging or clock drift, but the receiving rate of the receiving device is fixed, which may cause the received 429 data error;

[0007] 3) Troublesome debugging: When the sending rate of the sending device changes, the conventional method is to measure the sending rate of the current sending device with an oscilloscope and then modify the related program of the receiving device's receiving rate, which is slow and inefficient.

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