JPS6177450A - Interface converter - Google Patents

Abstract

PURPOSE:To attain effective transmission of a signal of the V24 200 series standards by introducing an interface converter between a CPU and an NCU. CONSTITUTION:The CPU11 transmits a parallel signal 23 of the V24 200 series to the interface converter 20. The converter 20 analysis the V24 200 series signal 23, encodes it and outputs the result as a V24 100 series signal 43. The signal 43 subjected to the V24 100 series is transmitted by using modulator- demodulators 91,92. The singal 23 outputted from a network controller NCU14 and transmitted to the interface converter 20 is converted into the V24 100 series signal and then transmitted conversely, and inverted by the interface converter 20 into the original V24 200 series signal 23 and given to the CPU 11.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is an interface conversion method used to interface a central control unit (CPU) and a network control unit (NCU) connected to a public network. Regarding equipment, especially 2
Consultative Committee on International Style Devotion (CCITT) Recommendation V, 2=1
The present invention relates to an interface conversion device used when transmitting information of 200 series signals using the public network.

[Conventional technology]

When performing data communication between the CPU and the terminal equipment (DTE), if a public network is available, there is no need to connect each CPU and DTE with cables, etc., and the public network will do it for you. Therefore, in areas where public networks are well-developed, the use of public networks provides a total of 9 incalculable advantages to data communication systems.

A public network is used for data communication between the CPU and the DTE, and network control units (NCUs) 14 and 15 are required, respectively. In addition, 16 and 17 are transmission lines for 100 series signals (serial signals) recommended by CCITT, 18 and 19 are transmission lines for 200 series signals (parallel signals) recommended by CCITT, and 21 and 22 are respectively transmission lines for modulation/demodulation equipment (MO).
DEM).

Here, CPU 11, NCU 14 and public network 12
When considering the investment effect in the case where there is a large distance between the two, the system configuration shown in Figure 3 is not the best, and the system configuration shown in Figure 4 may have a better meter reading effect. That is, in FIG. 4, MODEM 21 is located at substantially the same position as NCU l4.

[Problem that the invention seeks to solve]

In a system as shown in FIG. 4, where the distance between the CPU 11, NCU 21, and the public 12 is long.

In the prior art, signals specified in the 100 series of V, 24 can be transmitted using MODEM 21 or the like. However, the signals specified in the 200 series of V, 24 are parallel signals.

As the distance increases, the data characteristics deteriorate.

Moreover, there is a limit to the distance that the Zerarel Line can be drawn. No device is known that effectively transmits the 200 series signals of V,24.

An object of the present invention is to provide a device that can effectively transmit V.24 200 series parallel signal information when there is a large distance between the CPU, NCU, and public network.

In the following, [Means for solving the problem] The present invention is a parallel signal of 200 series of V, 24,
Convert to 24 100 series serial signals.

The present invention is also an interface conversion device characterized in that it converts a V, 24 (7) 100 SIJ-, etD serial signal into a 200 series parallel signal of V, 24.

That is, according to the present invention, a first interface circuit having a first input terminal for receiving a first parallel signal and a first output terminal for outputting a second parallel signal; a second interface circuit having a second input for receiving the first parallel signal and a second output for outputting a second serial signal; 1
an encoding circuit that receives a third parallel signal level-converted by the interface circuit, encodes it into a corresponding serial signal, and outputs it; a decoding circuit that receives a third serial signal that has been level-converted, decodes it into a corresponding parallel signal, and outputs it, and the second interface circuit level-converts the output signal of the encoding circuit. The second serial signal is outputted to the second output J terminal, and the first interface circuit converts the level of the output signal of the decoding circuit and outputs it as the second parallel signal to the first output terminal. An interface conversion device is obtained which is characterized by outputting to the output terminal.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, 11σ indicates that the interface conversion device 20 according to an embodiment of the present invention has a first input terminal [Nl, V, The second, which is the 200 series signal of 24
The first output terminal OUT for outputting the parallel signal 22 of
a first interface circuit (V, 2 of 24) with
007 Liz interface circuit): 3] and y, 24
a second input terminal IN2 receiving the first series signal 41 which is (No. 8) of 100 series, V, 24) 100
A second interface circuit (V, 24 100 series interface circuit) 52 has a second output terminal OUT 2 for outputting a second serial signal 42 which is a series signal.

The parallel signal 21 of the 200 series of V, 24 outputted from the CPU etc. is input to the 200 series interface circuit 31 of V, 24, and is converted to a TTL level that is easy to logically process by the primary encoding circuit 61. etc. (third parallel signal) 63 and sent to the encoding circuit 61. In this encoding circuit 61, the signal is sent from the interface circuit 31. The parallel signal information 63 of 200 lines is analyzed and fi, V,
V, 24 100 series is encoded into a serial signal that can be interfaced as transmission data of 24 100 series.
The output signal is sent to the printer's interface circuit 52.

(2) The 24/100 series interface circuit 52 converts the level of the output signal of the encoding circuit 61 and outputs it as a second serial signal 42 to the second output terminal OUT 2.

Conversely, V, 24 100 Norise interface circuit 5
The serial v, 24 100 series signal information 4■ inputted to the second decoding circuit 81 is converted into a signal (third serial signal) 83 at a level that can be processed by the secondary decoding circuit 81.
sent to. In the decoding circuit 81, this serial signal 83
is analyzed and decoded into a parallel signal of 1 element V and 24 200 elements.

(2) Level conversion is performed so that it can interface with the 200 series interface circuit 31 of 24, etc., and the signal is sent as a second parallel signal 22 from the first output terminal OUT 1 to the CPU, etc.

FIG. 2 shows a system configuration diagram using the interface conversion device 20 of the present invention. In fig.

23 represents a set of signal lines for transmitting the signals 21 and 22 in FIG. 1, and 43 represents a set of signal lines for transmitting the signals 41 and 42 in FIG.

It controls the NCU 14 and connects the terminal device (
(not shown), the CPU 11
200 series of parallel signals of V, 24 are sent to an interface conversion device 20 according to the invention.

As described above, this interface conversion device 20 analyzes and encodes the transmitted 200-series signal of V, 24, and outputs it as a transmission data signal of the 100-series signal of V, 24. .

■, the signal encoded into 24 100 series.

By using modulation/demodulation equipment (MODEM) 91 and 92, etc., transmission becomes possible and is transmitted to interface conversion equipment #20 according to the present invention. In addition, MODEM91
and 92 are connected by a wired line. In this interface conversion device 20, 100 of 24
V,2 encoded in the transmission data of the series signal
Decode the information of the 200 series signal of 4, V, 2 of 24
As a 00 series signal.

Output to NCU 14.

The 200-series IJ-language of v, 24 output from the NCU 14 and transmitted to the interface converter 20 is also converted to this interface converter 20 by the same means.
V, 24 is converted into a 100 series signal in the interface converter 20 through the modem and modulators 92 and 91.
is transmitted to the interface converter ξ20 and converted back to the original 200 series signal of V,24,
It is transmitted to the CPU 11.

It can be seen that the above operation enables data communication even in the system configuration shown in FIG. 944.

〔Effect of the invention〕

As explained above, according to the present invention, the CPU and the NC
When there is a considerable distance between U and the public network.

(2) Effectively transmits parallel signal information of 20 (1/l) of 24.

Furthermore, the interface conversion device according to the present invention has the effect of reducing the cost of investing in a public network.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an interface conversion device according to an embodiment of the present invention, and Fig. 2 is a block diagram showing an interface conversion device according to an embodiment of the present invention. Figure 3 is a block diagram showing the system when used. Figure 4 is a block diagram showing the system when the public network is used for data communication between the CPU and the terminal equipment (DTE). The figure is a block diagram showing a conventional system when the distance between CP[J and NCU is long. In Fig. 3. 20...Interface conversion device, 31...V, 2
4 200 series interface circuits, 52...v
, 24 100 series interface circuits, +61・
... Encoding circuit, 81... Decoding circuit.

Claims (1)

[Claims] 1. A first interface circuit having a first input terminal for receiving a first parallel signal and a first output terminal for outputting a second parallel signal; and a first serial signal. a second interface circuit having a second input terminal for receiving the first parallel signal and a second output terminal for outputting a second serial signal; an encoding circuit that receives a third parallel signal level-converted by the interface circuit, encodes it into a corresponding serial signal, and outputs it; and a second interface circuit that encodes the first serial signal at the second input terminal. a decoding circuit that receives a level-converted third serial signal, decodes it into a corresponding parallel signal, and outputs the same; The output signal is output as a second serial signal to the second output terminal, and the first interface circuit converts the level of the output signal of the decoding circuit and outputs it as the second parallel signal to the first output terminal. An interface conversion device characterized by outputting. 2, the first and second parallel signals comply with CCITT Recommendation V. 24
200 series signals, and the first and second series signals comply with CCITT Recommendation V. The interface conversion device according to claim 1, wherein the interface conversion device is a 100 series signal of 24.