JPH01175620A - Electronic equipment having keyboard - Google Patents

Abstract

PURPOSE:To reduce the number of keys by providing a discrimination means which discriminates whether an external device is connected or not and a processing means which executes a processing corresponding to the operation of a function key in accordance with the discriminated result. CONSTITUTION:A central processing unit 2 judges the key depressed in a keyboard 1. When it is judged to be a multifunction key, a signal is transmitted to an interface circuit I/F 5 through a signal line l2. When the printer of the external device is connected, the signal transmitted by the signal line l2 is fetched into the central processing unit 2 through a signal line l3 as it is. When the printer is not connected, the signals in the signal lines l2 and l3 do not coincide. With the decision, the central processing unit 2 decides the action of the multifunction key and displays memory contents in a display by the multifunction key or permits it to function as a print key. Thus, the number of the keys is reduced since the same key is separately permitted to function.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electronic device, such as a printer, having a detachable keyboard.

[Prior Art] Conventionally, this type of device has been equipped with dedicated keys for controlling the printer when a device such as a printer is connected, such as a print key, vapor feed key, and backfeed key. was.

[Problem that the invention seeks to solve] However,
The conventional example had the disadvantage that the main body became larger due to the increased number of keys.

The development of electronic technology in recent years has been remarkable, from LSI to ultra-L
Due to the shift to SI and improvements in mounting technology, devices are becoming lighter, thinner, shorter, and smaller at a rapid pace.

Under these circumstances, there is a movement to make electronic devices themselves smaller.

Therefore, the focus is on reducing the size of the keyboard, and the most important point is how to reduce the number of keys and make the keyboard compact.

However, as the functions of electronic devices have increased and the number of external devices has increased, the number of keys has increased.

[Means for solving the problem (and operation)] In order to solve this problem, the present invention determines whether or not a device such as a printer is connected, and according to the result of the determination, a It is equipped with processing means for performing corresponding processing.

[Example code] FIG. 1 is a block diagram of the present invention.

FIGS. 2 and 3 show an external view of the keyboard and a flowchart of the present invention.

In Fig. 1, 1 is a keyboard for inputting data and issuing processing instructions, 2 is a central processing unit that performs calculations and control, and 3 is a storage unit for controlling a control program according to the flowchart shown in Fig. 3. 4 is a read-only memory, 4 is a random access memory, 5 is an interface circuit for connecting an external device, and there is a means for determining whether or not an external device is connected. 6 is a connector for connecting and disconnecting the cable to the printer.

At present, the central processing unit 2 provides the address line AD to the read-only memory ROM 3 and is sequentially executing a program via the data bus line DB. The random access memory RAM 4 is used as a result of calculations performed by the central processing unit 2 and as a workpiece of the system.

Now, when the multi-function key of the present invention is pressed on the keyboard 1, the signal is taken into the central processing unit 2 via the signal line 1□.

The central processing unit 2 judges this key, and if it is judged to be a multi-function key, sends a signal to the interface circuit 1/F5 through the signal line 12.

If it is connected, the signal sent out through the signal line °C2 is taken in as it is to the central processing unit 2 via the signal line f13. Conversely, if they are not connected, the signals on signal line 12 and signal line 3 do not match.

Based on this determination, the central processing unit 2 determines whether the multi-function key is to be operated as a function key for an external device or as a separate function key for the main body alone.

The second is a general view of the keyboard, where 7 is a group of keys on the keyboard, and 6 is a multi-function key of the present invention.

If the main unit operates as a standalone unit, the memory contents shared with the printer will be displayed on the display (not shown), and if an external printer is connected to the main unit, it will function as a print key. do.

FIG. 3 is a flow chart of the present invention. In step 1, the central processing unit 2 constantly monitors key inputs via the signal line 1.

If no key input is made, the process waits for a key input, and if a key input is made, the process advances to step 2.

In step 2, it is determined whether the key pressed on the keyboard 1 is a multi-function key.

If it is not a multi-function key, the process proceeds to step 3, performs key processing, and ends the process.

Conversely, if the key is a multi-function key, step 4 is executed.

In step 4, a determination is made as to whether or not an external device is connected.

The central processing unit 2 has a logic circuit on it via a signal line.
is output, and the signal sent onto the signal line 12 from the signal line L3 is compared. If they do not match, it is interpreted that the external device is not connected, and the process proceeds to step 5 to load the memory.

Further, if the signals on the signal line I1.2 and the signal on the °C3 match, the central processing unit 2 outputs a logic “Φ” signal onto the signal line 12.

Here, the CPU 2 again connects the signal line f! , 3, and compare and match.

If they do not match, proceed to step 5 as before; if they match, proceed to step 6, print out to the printer, and end the process.

[Effects of the Invention] As explained above, by determining the presence or absence of an external device, the same key can be used for different functions, resulting in the effect of reducing the number of keys.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the present invention. Figure 2 is an external view. FIG. 3 is a flowchart. 1-11 keyboard 2----CP U3 ---
--ROM 4----RA M5
-111 interface circuit and detection circuit 6.7--
--key

Claims (1)

[Scope of Claims] A keyboard for inputting data; a function key provided on the keyboard; a determining means for determining whether an external device is connected in response to an operation on the function key; An electronic device having a keyboard, comprising: processing means for performing processing corresponding to the operation of the function key according to the determination result of the determination means.