JPS6284364A - Program developing device - Google Patents

Abstract

PURPOSE:To change the function of an evaluation chip through the changeover of circuit wiring by controlling the evaluation chip where a changeover circuit for selectable functions is incorporated or mounted externally by a control circuit. CONSTITUTION:The evaluation chip 1 where almost the same function as that of a microcomputer is provided and a changeover circuit is incorporated to the changeover part of wiring or mounted externally, a latch 2 selecting the functions of the evaluation chip, a control circuit 3 controlling the latch 2, and a memory 4 storing a data selecting the set function at the program development of the microcomputer are provided. The circuit reads a data instructing a function from the memory 4 and stores a prescribed data to the latch 2. The function is changed by instructing the circuit 3 for the change and rewriting a data for the latch only controlling said function.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a program development device for a microcomputer that switches wiring during manufacturing based on predetermined specifications.

(b) Conventional technology In general, one-chip microcomputers have a built-in ROM (read-only memory) for storing programs, and programs created by the user etc. are written using a mask when the one-chip microcomputer is manufactured. It will be done. When creating a program in advance, a program development device called an EVA 17 chip, which has a built-in combinator which has substantially the same functions as a manufacturing microcomputer, is used by the software and users.

By the way, one-chip microcomputers are provided with functions that can be freely selected according to the user's requirements. Specifically, when the power is turned on, the display can be turned on or off, the frequency of the system clock can be changed, and the frequency of the built-in timer can be changed.

It has functions such as switching the chattering prevention time of the switch input, switching the rising or falling operation of interlaced signals, and switching whether the input/output terminal is used only for output or for input. These functions are achieved by switching the wiring using masks when manufacturing microcomputers.
Selected.

When creating or evaluating a program to be programmed into the above-mentioned microcomputer, the evaluation chip is wired with resistors, jumper wires, etc. to achieve a prespecified function.

Such a program development system for a microcomputer is described on pages 51 to 67 of "Microcomputer Material Series NQ13rLc6500 Series User's Manual" published by the applicant on November 30, 1988.

Pj Problems to be Solved by the Invention However, in conventional program development devices, jumper wires, resistors, etc. had to be wired externally one by one to select functions, and wiring errors often occurred. Furthermore, when changing functions due to program changes, etc., wiring must be redone, which has the disadvantage of requiring a long program development time.

B.) Means for Solving the Problems The present invention has been made in view of the above-mentioned problems, and provides an evaluation tester with a built-in or external switching circuit for switching functions selectable by the user. A plurality of latch circuits that control the switching circuits, and a control circuit that applies switching data to the latch circuits based on data that instructs selection of a function can select a function created in advance by a user or the like. According to the instructed data, it can realize the same functions as a microcomputer for automatic button production.

(e) Effect: According to the above-mentioned means, data for selecting functions set at the time of program creation of the microcomputer is stored in a storage device (eg, magnetic disk, RAM).

The selection instruction data read out from the storage device is subjected to predetermined processing and applied to a latch circuit for storage. The output of the latch circuit then controls the switching circuit to route internal circuitry to implement the selected function.

(f) Embodiment FIG. 1 is a block diagram showing an embodiment of the present invention.
．． 1 is an evaluation chip, (2) is a latch circuit, (3) is a control circuit, and (41 is a storage device for storing selection instruction data).

The evaluation chip (1) has almost the same functions as a production microcomputer, but instruction codes are applied from the outside through terminals, and various internal data can also be read out from the terminals. be. Furthermore, a terminal (5) for applying a signal for controlling a switching circuit for switching user-selectable functions and a terminal (7) to which a switching circuit (6) for switching functions is externally connected are provided. A latch circuit (2) is provided corresponding to switching of each function,
Each output Q is connected to a terminal (5) and a switching circuit (6). In addition, the input of the latch circuit (2) is the control circuit (
3), and the clock terminal 2 receives the timing signal, d,,02, output from the control circuit (3).
...is connected to... The control circuit (3) reads data instructing functions created by, for example, a microcomputer and stored in a storage device (4), processes the data, and processes the switching circuit built in the evaluation chip (1) and the external circuit. Data for controlling the connected switching circuit (61) is stored in each latch circuit (21).

FIG. 2 shows an example of functions and switching circuits built into the evaluation chip (1). A clock Q created in an oscillator circuit by an externally connected crystal oscillator (8) and capacitor (9). is applied to the frequency divider circuit αυ. Further, the clock Q0 and the clock Q divided by the frequency dividing circuit OD are respectively applied to the transmitting gate (13Q4) constituting the switching circuit Z.

The output of the switching circuit α2 is applied to a timing generator α9 that generates system clocks T, -Tn for operating the computer. Therefore, the switching circuit (121
In this case, two types of cycle times can be selected by selectively applying clock pulses Qo and Ql to the timing generator (2).

In addition, the clocks Q2 and Q output from the frequency dividing circuit αυ
3 is applied to the transmission gate α71u& constituting the switching circuit (16), and the output of the switching circuit [61] is
Applied to the input of timer counter σ3. Therefore, by selectively applying clock pulses Q2 and Q to the switching circuit (161), the frequency of the timer can be switched.

On the other hand, in order to switch the input terminal between oven-type pressure and clocked pull-down type, input terminal Cυ
Transmitter gate that switches whether to apply the output of the inverter Q or the ground potential to the gate of MO8FETC231 connected between
A switching circuit consisting of □□ is provided.

These switching circuits (12 (161@) are controlled by the switching circuit 074 (leA@ Each transmitsucon gate 00 turn α7) bet and (c) ■ are external terminals @ (c) (
7).

Therefore, in FIG. 1, the control circuit (3) reads out data instructing functions from the storage device (4) and stores predetermined data in the latch circuit (2), so that, for example, the external terminal ( Assume that ``1'' is applied to 2), 0'' is applied to the external terminal (C), and 1'' is applied to the external terminal (7).

Then, in the switching circuit α2, the transmission gate α is turned on and the clock Qa is selected and applied to the timing generator α9, so that a function with a fast cycle time is selected. Further, in the switching circuit αGK, the transmission gate αη is turned on and the clock Q3 is applied to the timer counter 2, thereby realizing a timer based on a low frequency. On the other hand, in the switching circuit, the transmission gate is turned on, so the gate of MO8FET and the output of inverter t24 are connected, and the clocked pull-down function is selected. In this way, the designated function is automatically realized based on the data specifying the selection of the function.

By the way, when the program development device is operating by impersonating a function based on the data that selects and instructs a predetermined function stored in the storage device (4), if you want to change a part of the function for some reason, When the control circuit (3) is instructed to change the location, the control circuit (3) can rewrite data only in the latch circuit (2) whose function is being controlled. This results in
Program development using changed functions can be performed immediately.

(G) Effects of the Invention As described above, according to the present invention, there is no need for wiring to realize functions based on the user's specifications.

Eliminates wiring mistakes. Furthermore, since it is easy to change functions during program development, the program development period is shortened, and the microcombeater has the advantage of being produced and shipped quickly.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a circuit diagram showing an example of the functions in the block diagram shown in FIG. Explanation of main drawing numbers +11...Evaluation tip, (2+
...Latch circuit, (3) ...Control circuit, (4
)···Storage device. Rule n---g, ν keype

Claims (1)

[Claims] 1. ROM that stores programs (read-only)
A program development device for a microcomputer that has a built-in ROM (memory), a program is written into the ROM during manufacturing, and wiring is switched using a mask based on predetermined specifications, which has substantially the same functions as the microcomputer. an evaluation chip having a switching circuit built-in or externally attached to the switching portion of the wiring, a plurality of latch circuits controlling the switching circuit, and switching to the latch circuit based on data instructing switching of the wiring. A program development device characterized by comprising a control circuit for applying data and realizing functions similar to a microcomputer with predetermined specifications.