SU1335971A1 - Information input device - Google Patents

Abstract

The invention relates to computing and can be used in various equipment for the preparation and input of information, in particular in keyboard consoles of process equipment. The aim of the invention is to increase the reliability of the device while simultaneously pressing a few keys. The device contains a keyboard 1, a multiplexer 3, a counter 4, a ready signal generation unit 5, a register 14, keyboard polling blocks 15, a decoder 16. The device eliminates failures occurring during keyboard key switches and samjiTy from chatter, thereby increasing the reliability of the device. 1 hp f-ly, 3 ill. co

Description

1I

The invention relates to a computational technique and can be used by 13 different preparation and preparation data points, in particular, in particular (/ g, in keyboard consoles of those) equipment for assembling integral circuits.

The purpose of the invention is: 1naguing the operation of the device while simultaneously pressing a few keys. Figure 1 is a diagram of the device for entering information; FIG. 2 is a diagram of a keyboard polling unit; FIG. 3 is a time diagram of the operation of the device for entering information.

The device for entering information contains a T-key keyboard 1 (Fig. 1), each of which is connected to the device busbar with one output and the second to one of the keyboard inputs 1, of which through a corresponding load element 2 is connected to the power supply pin. devices, multiplexer 3, first counter A, block 5 forming a ready signal, first 6 and second 7 elements OR NOT, second counter 8, pulse shaper 9 third counter 10, first decoder 11, RS flip-flop 12, element 13 and register 14, m blocks 15 keyboard polling, the second decoder 16, the synchronous input 17 of the device, gating the output 18 of the device, the information outputs 19 of the device.

Each of the keyboard polling units 15 (FIG. 2) contains the first 20 and second 21 elements AND, the second 22 and third 23 NOT elements, the OR element 24 and the EXCLUSIVE OR element 25.

The information input device operates as follows.

Each of the keyboard polling units 15 (FIG. 1) has three inputs 26.28 and 29 and two outputs 27 and 30. The first INPUT and output are informational and are used to transmit data on the state of the t-key keyboard 1 to the multiplexer information inputs 3, the second input and output are control ones and are intended for organizing priority polling of the keys of the t-key keyboard 1, while the third input is a block select input. When Log.O is on this input, the block is turned off, and on both of its outputs the potential of Log.1 is formed, in the case of Log.1, on the third input, the block is 0.

0

five

0

five

0

five

The selection of and the output of its outputs now depends mainly on the signal on the second input of the block. Submission of the Log.O to this input will lead to the formation of the Log. on the first and Log.O on the second outputs of the block. The first shows that the status information of the switched key is not transmitted to PA multiplexer 3, while the second serves to prohibit the operation of all subsequent keyboard polling units 15.

Indeed, since the second output of each of the keyboard polling units 15 is connected to the second input of the keyboard polling unit 15 next to it, the Log.O. that appears on this output will automatically determine the Log. About the second output of the block following it, etc., up to П1-ГО of the block 15 of the keyboard survey. Therefore, by applying to the control input of the first block 15 of the keyboard polling Potential1, the Log.O has fallen, you can prohibit the operation of all the blocks 15 of the keyboard polling. In the case of Log.1, the state of both of its outputs is determined by the state of the first input, i.e. the state of the key of the t-key keyboard switched by this block 1. When the key is pressed, the potential of Log.O is formed on both outputs, and when released, the Log. one . Thus, with Log.1 of the second and third inputs of the keyboard polling units 15, the latter are completely determined by the state of the keyboard key 1 itself. This is the basis for organizing priority to poll the keys of the keyboard keyboard 1. For example, pressing of the second key will result in the appearance at the second output of the kth block of the keyboard polling of the Log.O signal, which will prohibit the operation of all subsequent blocks with numbers from K + 1 to m. This will exclude the possibility of transmitting several key activation signals when they are at the same time pressed, with the highest priority will be the key with the lowest number.

Let us examine this in more detail. Let, for example, simultaneously press the 0-, k- and t-clavgalis of the t-keyboard keyboard 1. Since at the second output of the 0th block of the I5 poll of the keyboard, the potential of Log.O is formed, this will lead to the fact that the same potential is observed at the second outputs of all the other blocks of the 15th poll of the keyboard, including K-1 and t -1st. This means that at the second inputs of the k-th and m-th blocks 15 of the keyboard poll, there will be signals from the Log.O that will switch the first outputs of these blocks to the State of Log.1. Thus, it can be seen that the signal of the Log.O from switching on the keys will be transmitted to the information inputs of multiplexer 3 only by the 0th block 15 of the keyboard poll, which was to be proved.

Let not one of the keys of the keyboard 1 be pressed at the initial moment of time, the potential of Log.1 is set at the control input of the first keyboard polling unit 15 and the RS-flip-flop 12 is in the off state. Then the high potential at its inverse output prohibits the operation of the second decoder 16, at the outputs of which the potentials Log.1 are set. Since the three inputs of the 0th keyboard interrogation unit 15 contain high levels of signals, the potentials of Log.G are also set at both of its outputs, which leads to the establishment of the same levels at the outputs of all other blocks of the 15th keyboard interrogation, up to the tth. Thus, in the initial state, all keyboard polling units 15 are selected, their operation is enabled, and they translate the states of the keys of the T-key keyboard 1 to the information inputs of the multiplexer 3.

Pressing any key of the t-key keyboard 1 will lead to the prohibition of the operation of those polling blocks of the keyboard, the number of which is greater than .number of the pressed key, and to the appearance of the potential Log, o on the corresponding information input of multiplexer 3. Poll of the t-keypad 1 is performed when the first counter 4 forms the corresponding address for the multiplexer 3. The first counter 4 is controlled from the source of clock pulses via the synchronous input 17 When the first counter 4 selects the input of the multiplexer 3 with the potential Log .o, the voltage the output of multiplexer 3 also becomes equal to

voltage Log.O for a time equal to one period of clock pulses. Thus, if the interrogated key of the t-key keyboard 1 is pressed continuously, then the output of the multiplexer 3 produces a sequence of pulses with a period T. T T and a duty cycle

QHM GP

where Tu is the period of pulses produced by the t-channel multiplexer 3; T .., - the period of the input clock imG and

pulses; m is the number of channels of t-channel

multiplexer 3;

0. the duty cycle of the pulses generated by the t-channel multiplexer 3. It follows that the keyboard vibration will be expressed by the presence of 3 pulses at the output of the multiplexer with a period longer than T "and a duty cycle greater than Q. Also, since the keyboard bounce has an unpredictable character, it should be noted that pulses with a period greater than T ,, at the output of multiplexer 3 can move with pulses with a period equal to T ,. Therefore, in order to fix the actual moment of operation of the keys of the t-key keyboard 1 with a sufficient degree of accuracy, it is necessary for the device to distinguish a sequence of moving pulses with different periods from a sequence of pulses with a constant period equal to Tj ,. In the proposed device, this is accomplished by setting a certain number of pulses with a period T not alternating with the pulses of a larger period. This number is generally determined empirically, but practice shows that 16 pulses with a period T, are sufficient for reliable operation of the device.

In the proposed device, the selection of larger than T is made by the second counter 8, the setting of the number of pulses with a period equal to T is the switching of the output of the first decoder 11, and this number is counted by the third counter 10. This is done as follows. The pulse shaper 9 generates pulses on the negative front of the input, clock pulses. The duration of these pulses is chosen to be shorter than the duration of the input clock of the Second Element OR NOT 7, which performs the AND function at zero, transmits those pulses of the former 9 pulses that coincide with the output pulses of multiplexer 3, and the first element .Sh1I-NOT 6 also performing the function AND by zero are those pulses of the imaging unit 9 pulses that do not coincide with the output pulses of multiplexer 3, for which the output of the latter is inverted by the element NOT 13. It is easy to see that the number of pulses transmitted by the first The element OR is NOT 6, is equal to the duty cycle of the output pulses of the multiplexer 3 minus one .. The pulses from the output of the first element STIS-NOT 6 are considered the second counter 8. Since the latter is whipped with each pulse of the second element OR-NOT 7, the pulse on its the output of the transfer can occur only if the number of pulses produced by the first element OR NOT 6 is greater than Q | ,, i.e. when the output pulses of the multiplexer 3 are greater than Q, t. The pulse from the transfer output of the second counter 8 clears the third counter 10 and sets the RS flip-flop 12 to zero. The pulses from the output of the second element OR NOT 7 are counted by the third counter 10. When the information reaches in it, the value commuted by the first decoder 1, at the output of the last, a pulse setting RS-flip-flop 12 into one state was determined, determined the moment of operation of the t-keyboard keyboard 1. Positive difference from the direct output RS-trig Hera 12- records the code of the interrogated key from the outputs of the first counter 4 to the register 14 and enters the gate 18 of the device, thus signaling to the external device that the information is ready and the time when the key has been activated. At the same Low potential from the inverse output of the RS flip-flop 12 allows the second decoder 16 to work, which decrypts the code of the polled key recorded in register 14. At the same time, on all outputs of the second decoder 16, besides, the number of which corresponds to the number of the polled key , the potentials of Log.O are established, and at this output is the potential of Log.G. Thereby, all keypad polling units 15 are turned off except for the one that is currently polling the key pressed. When the polled key is released, the first transfer pulse from the output of the second counter 8 will again set RS-flip-flop 12 to the zero state, and the device will go to the initial position, ready for polling the t-key keyboard 1.

For convenience of convenience, an arbitrary case is taken in which, while the number of specified pulses with a period is equal to 3.

The pulse shaper 9 generates pulses 32 (FIG. 3) along the negative front of the input clock pulses 31. When you press, for example, the k-th key of the t-key keyboard 1 (FIG. 1) at the outputs of multiplexer 3 and the HE element 13, the series pulses, respectively, 33 and 34 (fig.Z) with the first period greater than, with subsequent periods equal and then again with a period greater than T ,. The first period is characterized by the bounce of the t-key keyboard 1 (Fig. 1) when triggered, the subsequent 33 and 34 (fig. 3) the steady state of operation of the t-key keyboard 1 (Fig. 1), and the last 35 (fig. 3 ) - bounce when you turn off the k-th key of the t-keyboard keyboard 1 (figure 1). When counting pulses 36 from the output of the first element OR NOT 6, the second counter 8 (FIG. 1) will issue a transfer pulse 37 (FIG. 3) in the first period, which will confirm the zero state of the RS flip-flop 12 (FIG. 1) and clear the third counter 10. When the information in the latter reaches a value of three, the output of the first decoder 11 is a pulse 38 (FIG. 3), which sets the RS flip-flop 12 (FIG. 1) to one state. A positive differential 39 on its direct output (Fig. 3) will bring the code of the k-th key of the T-keypad 1 (Fig. 1) from the outputs of the first counter 4 to the register 14. When the k-key is released, the first the same skew pulse 37 from the output of the second counter 8 (Fig. 3) will again set the RS flip-flop 12 (Fig. 1) to the zero state.

Consider the case of switching multiple clamps. Let the 0n and the kth keys of the t-key keyboard 1 (Fig. 1) be switched. At the same time, at the first moment of time, let the k-key be pressed, then let the 0-key be pressed so that for a certain period of time both keys will be pressed, and then the k-key will be released and only 0- will remain on. When the k-key is pressed, in accordance with the described route, the pulses from the output of the first decoder 11 will turn on RS-flip-flop 12, and the information about the key code will be entered in register 14. The signal from the inverse of RS-flip-flop 12 will allow the second decoder 16 to work. which turns off all blocks of the 15 polls of the keyboard except for k-th. Therefore, the subsequent pressing of the 0th key will not lead to any changes in the device. This position will remain as long as the K key is turned off and the device does not respond to this action by turning off the RS flip-flop 12. Only after this, the 0th keyboard polling unit 5 will return to the selected state and will be able to transmit The 0th key on the information input of the multiplexer 3. At the next polling cycle of the t-key keyboard 1 by multiplexer 3, pressing the 0th key will be detected and a new turn on of the RS flip-flop 12 and entering into the 14 register of the 0-key code will follow. From the considered example it is clear that in the case of switching several keys, the proposed device generates the necessary number of readiness gates of information signaling the switching to the external device, and provides reliable information about the codes of the switchable keys.

The use of the proposed device makes it possible to eliminate the malfunctions that occur earlier when switching the keys of the terminal, thereby increasing the reliability of the equipment, its performance and the yield of usable products.

Claims (2)

1. A device for inputting information, comprising a keyboard, a multiplexer, a readiness signal generating unit, a counter, a register, an output The multiplexer is connected to the information input of the ready signal shaping unit, the counting counter input and the clock input of the ready signal shaping unit are the synchronous input of the device, the counter outputs are connected to the multiplexer address inputs and the information inputs of the register, the outputs of which are the information outputs of the device, the first output of the signal conditioning unit readiness is connected to the register clock and is a strobing output of the device, characterized in that In order to operate the device by simultaneously pressing several keys, a descrambler and keyboard polling blocks are entered in it, information inputs of which are connected to keyboard outputs, polling information outputs are connected to information inputs of a multiplexer, register outputs are connected to information inputs of a decoder, the second output of the signal conditioning unit ready is connected to the gate input of the decoder, the control input of the first polling unit is the device enable input, the output control Each polling unit is connected to the control input of a subsequent polling unit, the depressor outputs are connected to the corresponding inputs of the polling unit selection. 2. The device according to claim 1, wherein the polling unit comprises two elements AND, two elements NOT, element OR, element EXCLUSIVE OR, the output of which is the information output of the block, the output element OR is control The first output of the first element AND is the information input of the block, the output of the first element AND is connected to the first inputs of the OR element and the EXCLUSIVE OR element, the first input of the second element AND and the input of the first element are NOT the block select input, the output of the first element is NOT connected to the second in the OR element, the second input of the second element AND is the control input of the unit, the output of the second element AND is connected to the second input of the first element AND, and the input of the second element NOT, the output of which is connected to the second input of the element EXCLUSIVE OR 2 ® mimjiJimmruinjimmjin j @TGOT1GG1GT1PGT1G 22 25 FIG. g fig.Z