CN102567693B

CN102567693B - Method for processing abnormal command by ultrahigh-frequency tag

Info

Publication number: CN102567693B
Application number: CN201010622302.4A
Authority: CN
Inventors: 沈红伟; 张建平; 苏伟
Original assignee: Beijing CEC Huada Electronic Design Co Ltd
Current assignee: Beijing CEC Huada Electronic Design Co Ltd
Priority date: 2010-12-27
Filing date: 2010-12-27
Publication date: 2014-08-27
Anticipated expiration: 2030-12-27
Also published as: CN102567693A

Abstract

The invention discloses a method for processing an abnormal command by an ultrahigh-frequency tag. In the method, the tag judges the correctness of the received command, if the length of one or more bits of the command is abnormal, the tag ignores the command, and a state machine keeps the current state and waits for a reader to send the next command. The method can realize the following aims of: ensuring that the state machine of the tag cannot be halted even if the tag receives the abnormal command; 2, ensuring that the tag only ignores the current error command and still can correctly process the subsequent commands; and 3, ensuring that the tag can judge whether the command is abnormal at any time and immediately recover the decoding state to the initial state.

Description

The disposal route of a kind of ultrahigh-frequency tag to abnormal order

Technical field

The present invention is the disposal route of a kind of ultrahigh frequency electronic tag to abnormal order, and this invention is applicable to ultrahigh frequency electronic tag logical design field.

Background technology

When reader and label communication, because carrier wave is interfered, the correct order that reader sends may become abnormal.In the time that label receives disturbed abnormal order, must judge exactly the not correct order of this order, thereby ignore this order.Meanwhile, the state machine of label should jump to a correctly state, waits for that reader sends next command.

Summary of the invention

The object of the invention is to develop and a kind ofly can accurately judge current abnormal order, can correctly process again the method for follow-up correct order.Its implementation is as follows:

1,, to each data, quantize with system clock.

2, label detects that on data line, first low level is as delimiter, and quantized value is deli_cnt.

3, second data are tari, and quantized value is tari_cnt, if tari_cnt exceeds and the relativeness scope of deli_cnt, can think that this bit data is abnormal, and decoded state just resets, and the low level receiving so is again exactly delimiter.

4, the 3rd bit data is RTcal, and quantized value is rtcal_cnt, if rtcal_cnt exceeds and the relativeness scope of tari_cnt, can think that this bit data is abnormal, and decoded state just resets, and the low level receiving so is again exactly delimiter.

5, four figures is according to being TRcal, and quantized value is trcal_cnt, if trcal_cnt exceeds and rtcal_cnt, relativeness scope with tari_cnt, can think that this bit data is abnormal, decoded state just resets, and the low level receiving so is again exactly delimiter.

If 6 front four figures are according to all correct, what receive afterwards is all data, and quantized value is data_cnt, if data_cnt exceeds the relativeness scope with tari_cnt, can think that this bit data is abnormal, decoded state resets immediately, and the low level receiving so is again exactly delimiter.

7, make mistakes receiving arbitrary time, state machine does not change current state, waits reception next command, if detect next time and be still abnormal order, continues to wait for, until order entirely true.

If carrier wave is interfered, demodulator circuit likely receives wrong order at any time, and this wrong order may affect the reception of next command, and abnormal command handling method ensures that next command again can correctly receive.

Since the order of a correct code shape end up next command waveform as accompanying drawing two.

(1) 1,2,3 positions can only be data-0 or data-1.

(2), if delimiter command determination is 4 positions, correctly receive

(3) if delimiter command determination is 3 positions, the length of a should be tari, wherein the length of high level is T1 (two order interval), can judge that by implementation method 3 tari_cnt exceeds and the relativeness scope of deli_cnt, can jump to 4 positions automatically as delimiter

(4) if delimiter command determination is 2 positions, the length of b should be tari,

(5) if b is actual data-1, meet implementation method 3, can automatically jump to 3 positions as delimiter, revert to (1);

(6) if b is actual data-0, can not judge, a position is RTcal.Can judge that by implementation method 4 rtcal_cnt exceeds and the relativeness scope of tari_cnt, delimiter jumps to 4.

(7) if delimiter command determination is 1 position, the length of c should be tari,

(8) if c is actual data-1, can judge that by implementation method 3 tari_cnt exceeds and the relativeness scope of deli_cnt, can automatically jump to 2 positions as delimiter, revert to (4);

(9) if c is actual data-0, b position is RTcal.Can judge that by implementation method 4 rtcal_cnt exceeds and the relativeness scope of tari_cnt, delimier jumps to 4.

Brief description of the drawings

Fig. 1, command format, wherein:

1, first low level is delimiter,

2, bits per inch according to this rising edge finish,

3, clk is system clock, quantizes each data with it.

Fig. 2, completeness explanation

Embodiment

As shown in figure mono-, each data is counted with clk, and at each rising edge by under the value latch of counting, if this count value is in the scope of its permission, illustrate that this bit data is correct, if count value is less than its allowed band or has not also been greater than its allowed band to rising edge count value while arrival to rising edge, illustrate that this bit data is abnormal.

After occurring extremely, counter is zero clearing immediately, until next rising edge restarts counting again after arriving.

Claims

1. the ultrahigh frequency electronic tag disposal route to abnormal order, it is characterized in that, the header delimiter delimiter of every frame data that reader sends, minislot parameter tari, minislot parameter Rtcal, the length of minislot parameter Trcal four figures certificate is relatively fixing, each data is counted with system clock, and at each rising edge by the value latch of counting, judge that according to the relativeness of the length of adjacent two bits whether reception data are abnormal according to every frame head four figures, if this count value in allowed limits, illustrate that this bit data is correct, if count value is less than allowed band or has not also been greater than allowed band to rising edge count value when rising edge arrives, illustrate that this bit data is abnormal, counter is zero clearing immediately, until next rising edge restarts counting again after arriving.

2. the disposal route of ultrahigh frequency electronic tag as claimed in claim 1 to abnormal order, is characterized in that, the tari that second receives, and tari and delimiter have certain multiple relation, think that this bit data is abnormal if exceed this relation.