JPS6212635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a technique that allows attachment and detachment of additional units without adversely affecting the operating main unit.

In digital electronic devices, additional units such as keyboards and displays are often connected to the main unit as necessary. At this time, it is easy and convenient to connect both units while the power is on, but it is easy to cause malfunctions.

This is due to variations in the rise of the signal in the additional unit when power is started from the main unit to the additional unit when connected, variations in the timing of attaching/disconnecting each terminal of the connector when both units are attached/disconnected,
This is because signals are not transmitted from the additional unit to the main unit at accurate levels and timing due to noise generation when connecting and disconnecting connector terminals. To prevent this, it is possible to keep both units connected at all times, but this increases power consumption and there is also the risk of erroneously operating an operating switch on an additional unit that is not functionally necessary.

In consideration of the above points, the present invention provides a connection device that prevents each unit from malfunctioning even if an additional unit is connected at any timing to the main unit while the power is still on. In order to achieve this objective, the present invention monitors the connection status of the connector that connects both units, and further monitors the signal level of the connected additional unit, and when these are satisfied, the signal is transmitted between both units. It was designed to start. Examples will be described below.

In FIG. 1, 1 is a main unit which has a built-in power supply and operates independently regardless of the presence or absence of additional units. 2 is a control circuit consisting of a buffer gate with a control function, and 3 is a control circuit consisting of a buffer gate with a control function.
A gate circuit is composed of an AND gate (negative logic), and 4 is a connector consisting of a plug 4A and a receptacle 4B having multiple terminals. Reference numeral 5 designates a detection switch for detecting the attachment/detachment status of the receptacle 4B to the plug 4A, which is closed after all the terminals of the receptacle are inserted into the terminals of the plug 4A, and opened before the two terminals are separated when the receptacle 4B is removed. , so that the operating protrusion 5' (sensing portion) is located at the center of the connector 4 and on the separation line between the plug and the receptacle so as to detect the extraction operation. This operation protrusion 5' is operated by the receptacle 4B to close the detection switch 5 when the plug and receptacle are completely inserted as shown in FIG. 6 is a pre-up resistor that pulls the input terminal of the gate circuit 3 to level V (high level) so that it is not opened.

Reference numeral 7 denotes an additional unit, which is connected to the main unit 1 by a connector 4 as necessary to perform its additional functions. For example, a keyboard display that can be operated or displayed remotely corresponds to this. 8 is a plurality of signal line groups for transmitting signals between both units, 9 is an external connection signal line that transmits the signal level in the additional unit 7 to the control circuit 2 via the connector 4, and 10 is a signal from the detection switch. a signal line 11 that transmits the signal to the gate circuit 3;
is a signal line that transmits a connection information signal indicating the electrical connection state between both units from the gate circuit 3 to the main unit.

FIG. 3 is a circuit diagram inside the control circuit 2. As shown in FIG. In this circuit, one line is connected in series to each signal line of the signal line group 8.
Pairs of buffer gates 2A and 2B are provided, and each pair is oriented in opposite directions. Batsufua Gate 2
Depending on the level (high or low) of the signal sent from the main unit 1 to the DIL terminal, one of A and 2B is always in operation and the other is in an inactive state. Also,
Buffer gates 2A and 2B are also main unit 1.
When the level of the signal transmitted from the terminal to the H terminal is V and G (low level), the insulated state and the conductive state occur simultaneously. The operation of the embodiment having the above configuration will be explained. First, consider the case where the additional unit 7 is not connected. Receptacle 4 of connector 4
B is not inserted into the plug 4A, so the detection switch 5 is opened. The signal line 10 becomes level V, and similarly the signal line 9 also becomes level V, and the logic of the gate circuit 3 is not established, so that the level of the signal line 11 also becomes V.

Here, when the main unit 1 normally operates independently, it applies a V level signal to the H terminal of the control circuit 2 to turn off the buffer gates 2A and 2B, and the signal line group 8 before and after the control circuit 2 is electrically disconnected. It has a function to check the signal line 11 as necessary and determine that when this line is at the V level and GV level, it is an independent operation or an additional unit movement.

Next, when an additional unit is required, the receptacle 4B of the connector is inserted into the plug 4A. At this time, the timing of insertion and connection of the plurality of terminals within the connector is almost never simultaneous and is inconsistent. The detection switch 5 remains open until the connector is completely inserted, and the signal line 11 remains at the V level. When all the terminals inside the connector 4 have been inserted, the detection switch closes, and when the signal level inside the additional unit reaches a predetermined level that does not interfere with operation (in this case, we are looking at one level G of the power supply), Both signal lines 9 and 10 become G level, the logic of matching of the gate circuit is established, and the signal line 11
becomes G level.

Here, the main unit 1 detects the G level of the signal line 11, determines that it is interlocked with the additional unit 7, and supplies a G level signal to the H terminal of the control circuit 2, thereby turning the buffer gates 2A and 2B into a disconnected state. is released, and a signal is also given to the other terminal DIL to operate one of the buffer gates 2A and 2B, thereby transmitting a signal from one of the main and additional units to the other.

During this signal transmission, both units are completely connected via the connector 4, and the additional unit 7
Since each signal level, including the power supply level, has reached a steady state level, the level and timing of the signals transferred between both units is accurate, so that no malfunctions occur in either unit.

Since the time required for the signal line 9 to reach the predetermined level after the connector is connected is relatively short, if the connector is connected at normal speed in the above embodiment, the signal line 9 will reach the predetermined level before the detection switch 5 closes. It is something. Therefore, even if the level of the signal line 9 is not used as an input signal to the gate circuit 3, a certain degree of effect can be expected. However, since it is impossible to predict in what state and at what speed the connector connection will be made, the configuration as in the above embodiment is more reliable.

Furthermore, if configured as in the above embodiment, even when the additional unit is connected to the main unit, if the level of the signal line 9 is set to V by the switch provided in the additional unit, the main unit can be connected to the main unit. Units can also be operated independently.

Next, the case where the additional unit 7 is removed will be explained.
First, receptacle 4B of connector 4 is plug 4A.
When the sensor moves slightly away from the gate (however, all terminals of the connector 4 are connected at this time), the detection switch 5 is opened and one input of the gate circuit becomes the V level. The signal line 11 becomes V level and the main unit 1
is recognized as an independent operation, and the control circuit 2 is turned off. After this, each terminal of the connector 4 is released at different timings. When this terminal is separated, noise is generated, but since the control circuit 2 is briefly disconnected, it is not transmitted to the main unit 1, and malfunctions of the main unit can be avoided.

In the above embodiment, a contact switch is used as the detection switch 5, but it is not limited to this, and there is no need to use a photo interrupter or other proximity sensor, and the location is not in one place in the center of the connector, but near both ends of the connector. One detection switch may be provided, and the AND signal of these two detection switches may be used. In this case, the photointerrupter or the proximity sensor is arranged to be operated by at least one of the plug receptacles.

FIG. 4 shows another embodiment. This is connector 4
Terminals 41D at both ends of the terminals of plug 41A of No. 1
Make it shorter than the other terminal 41C. terminal 41
When the connector is connected, D is connected to the corresponding terminal in the receptacle 41B after the connection of the other terminal 41C is completed, and when the connector is removed, it is configured to be detached from the corresponding terminal in the receptacle 41B before the other terminal 41C is removed. . Therefore, the AND signal of the signals from the two terminals 41D may be input to the gate circuit 3.

In the above embodiment, the connecting device is provided on the main unit side from the connector, but the same effect can be obtained even if it is provided on the additional unit side, and in this case, unit 7 becomes the main unit. For example, if the unit 7 is a circuit using a CMOS element backed up by a battery, it is possible to prevent the latch-up accident peculiar to CMOS circuits, and protect the memory contents since the noise generated when the connector is connected is not transmitted.

As is clear from the above explanation, according to the present invention, additional units can be connected arbitrarily even when the main unit is in operation, so the connection work is extremely easy and does not require specialized knowledge. Malfunctions of the unit can be eliminated.

[Brief explanation of the drawing]

Fig. 1 is a circuit configuration diagram of an embodiment of the present invention, Fig. 2 is a diagram showing a connector, where A is a front view, B is a side view, Fig. 3 is a detailed view of the control circuit, and Fig. 4 is a diagram of the connector. FIG. 7 is a perspective view of another embodiment. 1: Unit, 2: Control circuit, 3: Gate circuit, 4: Connector, 5: Detection switch, 7: Additional unit.

Claims (1)

[Claims] 1. An additional unit that is interposed between the main unit and an additional unit that is connected to the main unit through a connector consisting of a plug and receptacle whose terminals are connected and separated by insertion and removal, so that signals between both units can be transmitted. In a connecting device for controlling transmission, a detection section is arranged on a separation line between the plug and the receptacle, and when both are fully inserted, the detection section is operated by movement of at least one of them. a switch means provided, a gate circuit which receives at least a basic signal from the above operation from the switch means and generates a connection information signal indicating the electrical connection state between both units, and a gate circuit which is interposed between both units and generates the connection information signal. What is claimed is: 1. A connection device comprising: a control circuit that operates in accordance with a command signal generated from a main unit upon reception of a control circuit for starting and stopping signal transmission between both units. 2. The gate circuit receives a signal from the switch means and a signal indicating the signal level of the additional unit transmitted via the connector, and is composed of a matching circuit that generates a connection information signal when both signals are generated simultaneously. A connecting device according to claim 1, characterized in that: