JPS6318432A - Information retrieval device - Google Patents

Abstract

PURPOSE:To speed up retrieving process, by performing retrieval in parallel with each bit of information to be retrieved and retrieving the bit position which is bit information of one side nearest to the bit, from which the retrieval is started. CONSTITUTION:If '1' is found in outputs PE0-PE7 of NOR circuits 17a-17h as the results of the 1st block 1, the output of an OR circuit 19 becomes '1' and the signal of the 2nd block 3 and is given to all NOR circuit of the 2nd block 3. Moreover, the output '1' of the circuit 19 is given to all NOR circuits of the 3rd and 4th blocks 5 and 7 through OR circuits 23 and 25. Therefore, all outputs PE8-PE31 of NOR circuits which become the results of the 2nd, 3rd, and 4th blocks 3, 5, and 7, become '0'. In such a way, the retrieved results of the blocks 1, 3, and 5 are respectively transmitted to the blocks 3-7, blocks 3 and 7, and block 7 in parallel with each other. Therefore, if '1' exists in the retrieved results of the block 1, the retrieved results of the block 7 become '0' irrespectively of the retrieved results of the blocks 3 and 5 and, as a result, the retrieval processing speed becomes higher.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention searches for the position of a bit that is one bit information that is closest to a search start bit of binarized search information. The present invention relates to an information retrieval device.

(Prior art) In search information composed of a plurality of "0'" and "1", first "0°" or "°" is searched in the search direction.
The method for detecting the position of the bit that is 1'' is to search the search information one bit at a time starting from the least significant bit or the most significant bit, and to determine whether it is 0 or 1'. A serial search method is used.

Figure 6 shows that search information consisting of multiple bits is searched from the least significant bit direction using a serial search method, the position of the bit that is “1°” is first detected, and that bit position is converted into a BCD code. 1 is a diagram illustrating the configuration of an information retrieval device.The information retrieval device shown in the figure includes a shift register 103 which is composed of a D-type flip-flop 101 and stores search information, an R8-type flip-flop 105, an AN
It has a D circuit 107 and a counter 109.

The shift register 103 is configured by connecting D-type flip-flops 101 in series, the same number as the number of bits of search information. Each D-type flip-flop 101 stores 1-bit search information, and the output of an AND circuit 107 is supplied to each clock CK. The shift register 103 shifts the search information stored in the D-type flip-flop 101 one bit at a time and outputs the result each time a clock is applied to the clock terminal GK of each D-type flip-flop 101.

The R8 type flip-flop 105 has its input R supplied with the output of the shift register 103, and its input S supplied with the search U11 signal. The R8 type flip-flop 105 has an output Q of 1' when the search start signal becomes "1".
', and when the human power R reaches "1°" in this state, the R8 type flip-flop 105 is reset and the output Q becomes "OII".

The AND circuit 107 has one input supplied with the output Q of the R8 type flip-flop 105, the other input supplied with the shift clock signal SCK, and the output from the clock terminal of each D type flip-flop 101. G
It is given to K.

The A N D circuit 107 is an R8 type flip-flop 10
When the output Q of the D-type flip-flop 101 is 1', the shift clock signal SCK is supplied to the clock terminal CK of each D-type flip-flop 101.

The counter 109 has its clock terminal CK supplied with a shift clock signal SCK via an AND circuit 107, counts up the number of shift clock signals SCK, and outputs the value in a BCD code. Further, a search start signal is applied to the reset terminal R of the counter 109, and when the search start signal reaches 1'', the counter 109 is reset and the counter 109 is cleared.

In such a configuration, when the search start signal becomes "1", the R3 type flip-flop 105 is reset,
The output Q becomes "1" and is applied to one input of the AND circuit 107.Furthermore, the counter 109 is also reset, the count value is cleared, and the search is started.

In such a state, each time the shift clock signal SCK is supplied to the clock terminal GK of each D-type flip 7O block 101 configuring the shift register 103 via the AND circuit 107, the search data stored in the shift register 103 is The information is shifted out one bit at a time and provided to input R of an R8 type flip-flop 105.

Furthermore, the shift 1-clock signal SGK is applied to the counter 10.
A counter 109 counts up the number of shift clock signals SCK.

In this way, the search information is being shifted bit by bit in synchronization with the shift clock signal SCK, and the bits shifted out from the shift register 103 and supplied to the input R of the R3 type flip-flop 105 are゛0
'', the output Q of the R8 type flip-flop 105 is in the "1°" state, and the shift clock signal SCK
is supplied to the shift register 103 and counter 109 via an AND circuit 107.

On the other hand, R8 is shifted out from the shift register 103.
If the bit supplied to the input R of type flip-flop 105 is 1°', then R3 type flip-flop 10
The output Q of 5 becomes “O”, and as a result, AND circuit 1
The output of 07 also becomes 0'°, and the shift clock signal @S
CK is no longer supplied to shift register 103 and counter 109.

Therefore, the shift operation of the shift register 103 and the counting operation of the counter 109 are stopped.

Therefore, by the time the counting operation is stopped, the shift clock signal @
The count value of scK represents the position of the bit that is "1" in the search information.

For example, if the search information is 4 bits long, 3 bits to 0
The bit is “'oioo” and the second bit is “1’°
, the shift register 103 is composed of four D-type flip-flops 101, and as shown in FIG. is shift register 1
Shift out from 03, R3 type flip-flop 1
The output Q of 05 becomes 0''. Therefore, the shift operation and counting operation are stopped by the third shift clock signal SCK, and the output of the counter becomes 'ooio', and the bit of the search information that is ``1n'' is The position of is detected.

(Problems to be Solved by the Invention) As explained above, in the serial search method, the search information is shifted one bit at a time by a clock signal, and the bit 11N, for example, is placed at the beginning of the search information. By counting the number of clock signals required to shift out, the position of the bit that is "1 pass" is detected.

In this way, since the search is performed by shifting the search information one bit at a time, the search time is reduced by the time it takes to search, for example, “
This depends on the position of the bit that is 1". For this reason, the search time is longest when, for example, searching information that has 1" only in the most significant bit is searched from the least significant bit, and if the search information is There was a problem in that it took a considerable amount of time to search when the search was made up of bits.

Therefore, this invention was made in view of the above,
An object of the present invention is to provide an information retrieval device that can perform a retrieval process at high speed without depending on the number of bits of retrieval information and the content of the retrieval information.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the information retrieval device of the present invention searches for each bit of retrieval information composed of a plurality of binary bits of information. a search means for searching in parallel from the least significant bit direction or the most significant bit direction, and detecting the position of the bit that is the one bit information closest to the bit at which the search is started; and converting means for converting the position of the bit corresponding to the BCD code into a BCD code as a relative position from the least significant bit.

(Operation) In the information retrieval device of the present invention, each bit of the retrieval information is retrieved in parallel from the least significant bit direction or the most significant bit direction, and one of the bits of information closest to the bit that started the search is retrieved. The position of the bit is detected, and this position is converted into a BCD code as a relative position from the least significant bit.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 are block diagrams showing an information retrieval device according to an embodiment of the present invention. This information retrieval device is composed of a retrieval section and a conversion section. FIG. 2 is a diagram showing the configuration, and FIG. 2 is a diagram showing the configuration of a converting section.

The information retrieval device in this embodiment includes 1'', 110
Search information that is binarized with I+ and consists of 32 bits,
°“ starting from the least significant bit or most significant bit direction.
It searches for the position of the bit that is 1'' and converts this position into a BCD code.

As mentioned above, the search unit shown in FIG. , all other bits in the search results are O''
shall be. For example, in 32-bit search information, the 0th bit and 1st bit are to11, and the 2nd bit is “°1”.
If the search information that is ``'' is searched from the least significant bit direction, the search result will be 1°' for the 2nd bit, regardless of the value of the 3rd to 31st bits of the search information. All bits become "0".

The search section is divided into four blocks, consisting of a first block 1, a second block 3, a third block 5, and a fourth block 7. In each block, when searching from the least significant bit direction, the first block 1 performs search processing for search information from the 0th bit to the 7th bit of the 32 bits of search information, and the second block 3 searches for the 8th bit to the 15th bit. The 1-th bit, the third block 5 searches for the 16th bit to the 23rd bit, and the fourth block 7 searches for the 24th bit to the 31st bit. Furthermore, when each block is searched from the most significant bit, the first block 1 searches from the 31st bit to the 24th bit, the second block 3 searches from the 23rd bit to the 16th bit, and the third block 5 searches from the 15th bit to the 8th bit. The fourth block 7, the fourth bit, performs a search process for the search information of the 7th bit to the Oth bit.

The first block 1 includes pass transistors 11a to 11h.
, 13a to 13h, inverter circuits 15a to 15h
It is composed of SNOR circuits 17a to 17h and an OR circuit 19.

Pass transistors 11a to 11h and pass transistors 13a to 13h are connected between a pass line 21 that provides search information to the information retrieval device and input terminals of inverter circuits 15a to 15h, respectively. The pass transistors 118 to 11h move from the pass line 21 to the O-th pit to the 7th pit according to the search signal in the search from the least significant bit direction.
Inverter circuit 15a for each bit of search information
~15h input terminal. The pass transistors 13a to 13h supply the search information of the 31st to 24th bits from the pass line 21 to the input terminals of the respective inverter circuits 15a to 15h by the search signal ~1 in the search from the most significant bit direction. be.

These pass transistors 118-11h, 13a-1
3h is composed of a circuit as shown in FIG. 3, for example. The pass transistor shown in the figure is a P-channel MOS transistor (hereinafter referred to as rPMO8J) 23 and an N-channel MOS transistor whose source and drain terminals are connected to each other.
It is composed of a channel MOS transistor (hereinafter referred to as rNMO8J) 25 and an inverter circuit 27. In the pass transistors 118 to 11h, NMO
A search signal is given to the gate terminal of 825, and P
A search signal is applied to the gate terminal of the MO 323 via the inverter circuit 27. Further, in the pass transistors 13a to 13h, a search signal QM is applied to the gate terminal of the NMO 825, and a search signal M is applied to the gate terminal of the PMO 323 via the inverter circuit 27.

In such a circuit configuration, when the search signal R or the search signal M becomes a high level state, the PMO 823 and the NMO 825 become conductive, and the search information is provided from the pass line 21 to the inverter circuits 15a to 15h, respectively. Therefore, pass transistors 118 to 11h
becomes conductive when the search signal becomes high level when searching from the least significant bit direction, and the search information of the 0th bit to 7th bit is transferred to the inverter circuits 15a to 15a.
Supply every 5 hours. In addition, pass transistors 13a to 13
h becomes conductive when the search signal M goes high when searching from the most significant bit direction, and the search information of the 31st to 24th bits is transferred to the inverter circuit 15.
Supply from a to 15h.

The outputs of the inverter circuits 15a to 15h are separately supplied to the respective inputs of the NOR circuits 17a to 17h, and the outputs of the NOR circuits 17a to 17g are supplied to the inputs of the NOR circuits 17b to 17h in the next and subsequent stages. ing. Further, inputs of the NOR circuits 17a to 17h are supplied with block signals for transmitting search results for each block to other blocks, and the first block is supplied with a block signal in a low level state.

The NOR circuits 17a to 17h output the search results of the 0th bit to 7th bit of the search information to outputs PEO to PE7, respectively, when searching from the least significant bit direction, and output the search results from the 0th bit to 7th bit of the search information to outputs PEO to PE7, respectively, when searching from the most significant bit direction. , search information 31
Outputs the search results for bits 1 to 24, respectively.
Output to E0-PE7.

The NOR circuits 17a to 17h determine whether the search information given to each input is 0" or "1", and the search information 0" from the pass line 21 is given to the NOR circuit via the inverter circuit. Then, the output of the NOR circuit becomes O''.

Furthermore, when search information of “1'' is given, if the outputs of all NOR circuits in the preceding stages of the NOR circuit to which this search information is given are “0”, lightning detection information of “1” is given. The output of the NOR circuit is 1''. Roughly speaking, since the output of the NOR circuit is given to the input of the NOR circuits from the next stage onward, the outputs of all the NOR circuits from the stage after the NOR circuit whose output is 1' are °°0''. Become.

For example, in a search from the least significant bit direction, if the 0th bit to 3rd bit of the search information is "0" and the 4th bit is 1'', then "0th bit to 3rd bit which is OIs" The bit-th search information is supplied to NOR circuits 17a to 17d corresponding to each bit of the search information via inverter circuits 15a to 15d, respectively, and outputs PEO to each of NOR circuits 178 to 17d.
PE3 becomes “0pa”.

Furthermore, the fourth bit of search information, which is "1", is supplied to the NOR circuit 17e via the inverter circuit 15e.

This NOR circuit 17 is connected to the input of this NOR circuit 19.
Since the outputs of all the NOR circuits 15a to 15d in the previous stage of e are given, that is, the NOR circuits 17a to 1
Since the outputs PEO to PE3 of 7d are given, NO
The output PE4 of the R circuit 17e becomes "1".

Furthermore, the output PE4 of the NOR circuit 17e, which has become 1'', is used in the subsequent stages of this NOR circuit 17e, that is, the NOR
Given to the inputs of circuits 17f to 17h, the 5th bit to
Regardless of the value of the 7th bit search information, NOR circuit 1
The outputs PE5 to PE7 of 7f to 17h are all "0'°.

The OR circuit 19 has NOR circuits 17a to 17h at its inputs.
The outputs PEO to PE7 are given, and a block signal is also given. This OR circuit 19
The search result of block 1 is transmitted to the second block 3, third block 5, and fourth block 7. That is, in the first block 1, the NOR circuits 17a to 17h
The outputs of PEO to PE7 are small (each one is 1''
If so, the search results for the second block 3 to fourth block 7 are all set to 0''.

The second block 3, the third block 5, and the fourth block 7 are
It is constructed similarly to the first block 1 and has the same features. Note that the fourth block does not have an OR circuit. The second block 3 provides the search results of the supplied search information to the output PEs 8 to PE15, and the third block 5 provides the search results of the supplied search information to the output PE 16.
-23, and the fourth block 7 provides the search results of the supplied search information to outputs PE24-PE31.

The block signal supplied to the second block 3 becomes the output of the OR circuit 19 indicating the search result of the first block 1, and the block signal supplied to the third block 5 becomes the output of the OR circuit 19 of the first block 1. and the output of the OR circuit of the second block 3 are output by the OR circuit 23, and the fourth
The block signal of the block 7 is the logical sum output of the outputs of the OR circuits of the first block 1, the second block 3, and the third block 5 from the OR circuit 25.

For example, in the search result of the first block 1, if the outputs PEO to PE7 of the NOR circuits 17a to 17h have 1°, the output of the OR circuit 19 will be "1", which means that the output of the OR circuit 19 will be "1".
This becomes a block signal for block 3 and is applied to all NOR circuits in second block 3. Further, the "1" output of the OR circuit 19 is given to the third block 5 and the fourth block 7 via the OR circuits 23 and 25, and is given to all the NOR circuits of the third block 5 and the fourth block 7. .

Therefore, the NOR circuit outputs PE8 to PE31 which are the search results of the second block 3, third block 5, and fourth block 7 are all r"o".

In this way, the search result of the first block 1 is sent to the second block 3 to the fourth block 7, the search result of the second block 3 is sent to the third block 5, the fourth block 7, and the third block 5.
The search results are transmitted to the fourth block 7 in parallel.

Therefore, for example, the search result for the first block 1 is "1".
′, the search result of the fourth block 7 is
Regardless of the search results of the 10th block 3 and the 3rd block 5, the result is IIO11, and the searched information is processed at high speed.

By the way, an example of the circuit configuration when the search information is processed by the serial method is not shown in FIG. The search process is performed by logically multiplying the search result and the AND circuit 27, and this search result is supplied to the next stage via the NOR circuit 29 and the inverter circuit 31. Although it is small,
When searching from the least significant bit, the search results are sequentially transmitted from the least significant bit to the most significant bit.

Therefore, for example, it is composed of 32 bits, the 0th bit to the 30th bit are 0, and only the 31st bit is 11.
1 When searching information that is IT is searched from the least significant bit, 30 NOR circuits 29 and 31 inverter circuits are required for the 31st bit output PE31 to be "1°". 31 delay times are required.

For this reason, high-speed search processing is difficult in the serial method.

However, in this embodiment, by processing the search information in parallel for each block, the search process can be performed in parallel.
It is done in a.

In the configuration shown in FIG. 1, for example, when only the ○th bit of the 32-bit search information is "0°" and all other bits are 1'°, the search process from the least significant bit is as follows:
After "°0°" is output to the output PEO of the NOR circuit 17a and "1" is output to the output PE1 of the NOR circuit 171), the outputs PE2 of the NOR circuits 17c to 17h are output.
〜P0°゛ is output to PE7 and OR circuit 19
The output of the gate becomes ``1'', then ``0'' is output to PE8 to PE15 of the second block 3, and the output of the OR circuit 23゜25 becomes ``1'', and the output of the third block 5 becomes ``1''.
, "0" is output to the outputs PE16 to PE31 of the fourth block 7.

Therefore, the delay time for obtaining the search result is NOR circuit 17a-+NOR circuit 171) → NOR circuit 17c~
N0RI 7h, OR circuit 19 → second blow (7)
NOR circuit, OR circuit 23. There are a total of five logic circuit valves, including the OR circuit 25 and the NOR circuits of the third block 5 and the fourth block 7, and the search process is performed at a considerably high speed.

Further, in this embodiment, the search information is processed block by block, but when searching the search information without dividing it into blocks, the output of the NOR circuit at the previous stage is processed by the output from the NOR circuit at the next stage. It is now supplied to the inputs of all NOR circuits.

Therefore, the outputs PE0 to PE30 of all the previous stage NOR circuits are supplied to the input of the final stage NOR circuit, and the final stage NOR circuit becomes a 32-manpower NOR circuit.

FIG. 6 is a block diagram showing an example of a multi-input NOR circuit. This NOR circuit consists of PMO833 connected in series with the same number as n inputs, and NMO833 connected in parallel with n inputs.
835, P M OS and NMO8
This is a commonly used circuit configuration for a NOR circuit using .

In such a configuration, when the output ○UT is set to 0'', it is necessary that at least one of the NMOs 835 becomes conductive, so if OII ratio output is performed relatively quickly.However, the output When OUT is set to ``1'', all n PMOs 8 must be rendered conductive, so that the output is considerably delayed compared to the n ratio output of ``1''.

Therefore, it is difficult for a NOR circuit with a multi-input configuration to operate at high speed. Therefore, in the search section shown in FIG.
Measures were taken to reduce the circuit input to about 9 human power and reduce the 1" output delay.

FIG. 2 is a diagram showing the configuration of the converting section, and this converting section is
OR circuits 37a to 37j, 39a to 39e, E
It has XOR (exclusive OR) circuits 41a to 41e1 and pass transistors 43a to 43e, and the search results are
This is to convert it into a CD code.

In the search result of 32-bit search information, the bit position that is "1" is represented by a BCD code according to the following equation.

a42' +a323+a222+a + 2'+a
02°Here, a4. a3. a2. al and aO are each 16
．． It has a weight of 8.4.2.1. For example, if the third bit of the search result is 1, a4=110u
, a3=1101Za2="O", a1="1", a
o = "1", and the search result is expressed as "00011°' in BCD code.

The OR circuits 37a to 37j have inputs of the NOR of the search section.
The outputs of the circuit PEO to PE31 are supplied. Specifically, the inputs of the OR circuit 37a are PEI, PE9, and PE.
17, PE25 are given to the inputs of the OR circuit 37b, PE2, PE10, PE18, PE26, and the inputs of the OR circuit 37C are PE3, PEI 1, PE19, P
E27, the input of the OR circuit 37d is PE4, PE12,
PE20. PE28 and PE5 are input to the OR circuit 37e.
, PE13, PE21, PE29, OR circuit 37f) Input 1. : PE6, PE14, PE22, PE30, O
The inputs of the R circuit 37a include PE7, PE15, PE23,
PE31 is given.

The inputs of the OR circuit 37h are PE8 to PE15, the inputs of the OR circuit 37i are PE16 to PE23, and the OR circuit 37j
PE24 to PE31 are given to the inputs of.

The OR circuits 398 to 39e have an input of the OR circuit 37a.
~37j outputs are supplied. Specifically, the inputs of the OR circuit 39a include OR circuits 37a, 37c, 3
7e, 37(+ output is given, OR circuit 3
The input of 9b includes OR circuits 37b, 37c, 37r.
, 37fJ and the input of the OR circuit 39c.
The outputs of the circuits 37d, 37e, 37r, 37g, the inputs of the OR circuit 39d are the outputs of the OR circuits 37h, 37j, the inputs of the OR circuit 39e are the OR circuits 37i, 37
The output of j is given.

The OR circuits 39a to 39e output the BC of the search results.
A D code is output. That is, the aforementioned BCD code ao is output to the output of the OR circuit 39a, al is output to the output of the OR circuit 39b, and a is output to the output of the OR circuit 39c.
2. A3 is output from the OR circuit 39d, and a4 is output from the OR circuit 39e.

The search signal M is applied to each negative input of the EXOR circuits 41a to 41e. EXOR circuit 41
The output of the OR circuit 39a is given to the other input of a, and the output of the OR circuit 39a is given to the other input of the EXOR circuit 41b.
9b, the other input of the EXOR circuit 41C is given the output of the OR circuit 39c, the other input of the EXOR circuit 41d is given the output of the OR circuit 39d, and the other input of the EXOR circuit 41e is given the output of the OR circuit 39e. It is being

By the way, when the search information is searched from the most significant bit direction, the search result for the 31st bit of the search information is PEO.
The search result for the 0th bit is output to the PE 31, and the search result is the opposite of the case where the search information is searched from the least significant bit. For example, in a search from the most significant bit direction, if the 31st bit of the search information is 1'', PEO is “1” and PE1 to PE
30 becomes 0', and aO to a4 are all 0'.

becomes. This indicates that the 0th bit of the search information is the 1st bit, and the search result does not represent the relative position from the 0th bit.

Therefore, when searching from the most significant bit direction of the search information, it is necessary to perform correction so that the search result is expressed as a relative position from the 0th bit.

This correction is performed when the search information is searched from the most significant bit direction.
This is done by reversing a4.

As mentioned above, if the 31st bit of the search information is 1'', aO to a4 are inverted and aO to a4 are all
If it is ``1'', the BCD code of the search result is ``11''.
11''. This represents 31 in decimal notation, and the search result will be expressed as a relative position from the 0th bit.

The EXOR circuits 41a to 41e perform the above-described inversion operation of aQ to a4 when searching from the most significant bit direction of the search information. When searching from the most significant bit direction, the search signal M is 1°°, so the EXOR circuit 41
a to 41e are the other input to the sono output, that is, a Q
An inverted signal of %a4 will be output. Also, when searching from the least significant bit direction, the search signal M is “0”.
Therefore, the EXOR circuits 41a to 410(7) outputs niha and a□ to a4 are output as they are.

The pass transistors 43a to 43e have the same configuration as the pass transistors 118 to 11h and 13a to 13h of the search section described above, and supply ao-84, which is the BCD code of the search result, to the pass line 45 by a bus signal. be.

As explained above, an actual example of the present invention is constructed, and the operation of this example will be explained next.

If the search information is searched from the least significant bit direction,
When the search signal level reaches 1 level, the pass transistors 118 to 11h become conductive, and the O-th to 7th bits of the search information are connected to the pass transistors 11a, respectively.
~11h and N via the inverter circuits 15a to 15h.
It is supplied to OR circuits 178-17h. Similarly, the 8th to 15th bits of the search information are the NO of the second block 3.
The 16th to 23rd bits of the search information are supplied to the NOR circuit of the third block 5, and the 24th to 31st bits of the search information are supplied to the NOR circuit of the fourth block 7.

Furthermore, when the search information is searched from the most significant bit direction, the search signal M goes to the "1" level, so that the pass transistors 13a to 13h become conductive, and the 31st to 24th bits of the search information are , pass transistors 11a to 11h and inverter circuits 158 to 15, respectively.
h to NOR circuits 17a to 17h. Similarly, the 23rd to 16th bits of the search information are sent to the NOR circuit of the second block 3, and the 15th to 8th bits of the search information are sent to the NOR circuit of the second block 3.
The 7th bit of the search information is sent to the NOR circuit of the third block.
The bits from bit 0 to bit 0 are supplied to the NOR circuit of the fourth block.

In each NOR circuit, search information °“O°′,”
A determination of 1° is made and if the search information is 0", the output of the NOR circuit becomes 0", and this output is supplied to the inputs of all NOR circuits from the next stage onwards.

If the search information is 1'', search from the least significant bit direction will search information lower than this search information, and search from the most significant bit direction will search information higher than the search information which is 1''. If all search information is 'O°', “
The output of the NOR circuit given search information that is 1'' is 1
'', and this output is supplied to the inputs of all NOR circuits from the next stage onwards.

When at least one of the outputs PE0 to PE7 of the first block 1 becomes "1", the output of the OR circuit 19 becomes "1", and the block signal of the second block 3 becomes "°1". 19's output is the OR circuit 23.
25, the outputs of the OR circuits 23 and 25 are both "1°", and the block signals of the third block 5 and the fourth block 7 are 1'°. The outputs PE8 to PE31 of the NOR circuits of block 5 and fourth block 7 all become O11.

Similarly, PEO to PE7 are all ○'', and the second
At least one of the outputs PE8 to PE15 of block 3
When the signal becomes "1", the output of the OR circuit of the second block 3 becomes "1", and the output of the OR circuit 23.25 becomes "1". As a result, the block signals of the third block 5 and the fourth block 7 become "1", and the outputs PE16 to PE31 of the NOR circuits of the third block 5 and the fourth block 7 all become "OII". is all “
On, and when at least one of PE16 to PE23 becomes 1'°, the output of the OR circuit 25 becomes 1",
All outputs of the NOR circuit of the fourth block 7 become "0".

In this way, the 32-bit search information is searched from the least significant bit direction or the most significant bit direction, and the output of the NOR circuit corresponding to the bit of the search information that is initially 1'' becomes 1''. The outputs of all other NOR circuits are "0", and the search results of the search information are PEO to PE3.
1 is output.

The search result of the search information is the output of the NOR circuit PEO~PE3
1, these outputs are output to the OR circuit 3 of the conversion section.
7a to 37j. PE9~PE157jPE
If any one of 0-PE7 is 1″, OR
The output of any one of the circuits 37a to 37g becomes 1゛°,
The output of one or more of the OR circuits 39a to 39c becomes 1". When PE8 is 1",
The output of the OR circuit 37h becomes 1'', and the output of the OR circuit 39 (l becomes 111 It).

Further, when any one of PE9 to PE15 is 1", the output of any one of the OR circuits 37a to 37g and the output of the OR circuit 37h become "1", and the OR circuit 3
Any one or two or more of 98 to 39c and OR
The output of the circuit 39d becomes 1"'. When PE16 is "1", the output of the OR circuit 37i becomes 1'°,
As a result, the output of the OR circuit 39e becomes "1".Furthermore, when any one of PE17 to PE23 is "1", the output of any one of the OR circuits 37a to 37o and the output of the OR circuit 37i The output becomes 1'°, and the output of any one or more of the OR circuits 39a to 39c and the OR circuit 39e becomes 1'.
'', the output of the OR circuit 37j becomes ``1'', and as a result, the outputs of the OR circuits 39d and 39e become 1''.
becomes. Furthermore, the output of PE25 to PE3.1 is
゛For 11 matches, any one of OR circuits 378 to 37g
The output of one or more of the OR circuits 39a to 39c and the output of the OR circuit 39d and 39e becomes "1".

In this way, the outputs of the OR circuits 39a to 39e become "1" in accordance with PE0 to PE31 which become "1", and the values of aO to a4 which become the BCD code of the search result are changed to the OR circuit 39a.
It is output from a to 39e.

The outputs of the OR circuits 398 to 39e are supplied to the EXOR circuits 41a to 41e, respectively, and when searching from the least significant bit direction of the search information, the search signal M becomes 0°, and the outputs of the OR circuits 39a to 39e respectively. The output is provided by EXOR circuits 41a to 41e and pass transistor 41 separately.
It is supplied to the pass line 45 via lines 8 to 41e. Further, when searching from the most significant bit direction of the search information, the search signal M becomes 1'', so each OR circuit 398
The outputs of ~39e are separately sent to EXOR circuits 41a~41e.
is inverted and supplied to the pass line 45 via pass transistors 433 to 43e.

In this way, the bit position that is “I Jl” is converted into a BCD code as a relative position from the Oth bit, and when the search starts, the bit position that is “1'' is It is searched and expressed as a BCD code.

Note that this invention is not limited to the above-mentioned embodiments,
It can be implemented in other ways by making appropriate changes.

[Effects of the Invention] As explained above, according to the present invention, each bit of the search information is searched in parallel from the least significant bit direction or the most significant bit direction, and the bit closest to the bit that started the search is searched in parallel. Since the position of the bit that is the bit information of the search information is searched, the position of one of the binarized bit information can be detected at high speed regardless of the number of bits of the search information.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the configuration of a search unit in an information search device according to an embodiment of the present invention, FIG. 2 is a block diagram of the configuration of a conversion unit in the information search device according to an embodiment of the invention, and FIG. A configuration diagram showing an example of a pass transistor,
FIG. 4 is a block diagram showing an example of a serial search method, and FIG. 5 is a multi-input N system. FIG. 6 is a block diagram showing an example of an R circuit, FIG. 6 is a block diagram showing a conventional example of an information retrieval device, and FIG. 7 is a timing chart of FIG. (Explanation of symbols representing main parts of the diagram) 1...First block 3...Second block 5...Third block 7...Fourth block

Claims (1)

[Claims] Each bit of search information composed of multiple pieces of binary bit information is searched in parallel from the least significant bit direction or the most significant bit direction, and one bit information closest to the bit that started the search is searched. and a conversion means that converts the position of the bit that is the one bit information into a BCD code as a relative position from the least significant bit. Information retrieval device.