JP2513888B2 - Microprocessor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microprocessor having a debug support function, and more particularly to a microprocessor providing means for assisting hardware debug in the development of a microprocessor system. It is a thing.

[Conventional technology]

FIG. 3 shows a conventional hardware debug environment of a microprocessor system. In FIG. 3, 11 is a microprocessor system, 1 is a microprocessor for data processing, 21 is an input / output signal line of the microprocessor 1, 6 is a logic analyzer for measuring signals, and 7 is a logic analyzer 6 for measuring signals. In order to do this, it is a measurement probe that is connected to the A line to F line.

Next, a debugging method will be described. In hardware debugging, check the signal line of the microprocessor 1,
The timing of each signal line is often verified. A logic analyzer 6 is used as the measuring device. When measuring, connect the signal line you want to measure and the signal line for setting the sampling start condition to the probe 7 of the logic analyzer 6.
Connect to and set the conditions for starting sampling of the signal line.

For example, consider a case where the signal timings of the E line signal and the F line signal shown in FIG. 4 from time T3 are examined. The probe 7 of the logic analyzer 6 is connected to the E line and F line to be measured and the A line, B line, C line and D line for setting the sampling start condition. At this time, the sampling condition is set in the logic analyzer 6 by a logical product of A line = '1', B line = '0', C line = '1', and D line = '1'.

[Problems to be Solved by the Invention]

When measuring a signal line with a logic analyzer in hardware debugging of a conventional microprocessor system, connect the probe to the signal line to set the sampling start condition in addition to the signal line to be measured. There must be. Also, when changing the sampling start condition, it is necessary to reconnect the probe and set the sampling start condition again.

The present invention has been made to solve the above problems, and an object thereof is to obtain a microprocessor capable of improving the debugging efficiency of hardware of a microprocessor system.

[Means for solving the problem]

The microprocessor according to the present invention wants to output from the signal measuring output terminal 3 for outputting the signal to be measured, the input / output signal terminal 2 for inputting / outputting the signal, and the signal measuring output terminal 3. A signal output control register 4 for setting a signal from the input / output signal of the input / output signal terminal 2 by software, and a signal output for outputting the signal set in the signal output control register 4 to the signal measurement output terminal 3 And means 5.

[Action]

The signal output control register 4 sets the signal to be output from the signal measurement output terminal 3 from the input / output signals of the input / output signal terminal 2 by software. The signal output control means 5 outputs the signal set in the signal output control register 4 to the signal measurement output terminal 3. Debugging is performed by the signal output from the signal measuring output terminal 3.

〔Example〕

FIG. 1 is a block diagram of a microprocessor according to an embodiment of the present invention. In FIG. 1, 1 is a microprocessor, 3 is a signal measuring output terminal for outputting a signal to be measured, 2 is an input / output signal terminal for inputting / outputting signals, and 4 is a signal measuring output terminal 3. The signal output control register for setting the signal to be output from the input / output signal of the input / output signal terminal 2 by software, 5 is the signal output for outputting the signal set in the signal output control register 4 to the signal measurement output terminal 3. It is a control means.

Next, the operation of this embodiment will be described. In this explanation, as in the conventional example, the signal of the E line and the F line shown in FIG.
Consider the case where the signal timing from the time T3 with the signal on the line is measured. First, the probe 7 of the logic analyzer 6 as shown in FIG. 3 is connected to the E and F lines of the input / output terminal 2 and the signal measuring output terminal 3 shown in FIG. Sampling start condition is logic '1' from signal measurement output terminal 3
The signal measurement output terminal = '1' is set in the logic analyzer 6 so that the signal of FIG. Next, by the software of the microprocessor 1, A line = '1', B line =
Set the signal output control register 4 so that a signal of logic "1" is output from the signal measurement output terminal 3 when the logical product of "0", C line = "1" and D line = "1" is established. To do. As shown in FIG. 2, the signal output control register 4 is assigned a field corresponding to each signal. Depending on the numerical value set in this field, output a signal of logic "1" to the signal measurement output terminal 3 when the signal is "0", or to the signal measurement output terminal 3 when the signal is "1". Output the signal of logic '1', or the signal is output terminal 3 for signal measurement.
Is irrelevant to the signal at. A line, B line, C
Signal output control register 4 for a plurality of signals such as lines, ...
If the field is set, the logical product of the fields makes the above determination. The signal thus set in the signal output control register 4 is read by the signal output control means 5 and the signal measuring output terminal 3 is read according to the above determination.
Output from By measuring the output signal with the logic analyzer 6 as shown in FIG. 3,
The hardware of the microprocessor 1 can be debugged.

As described above, since the microprocessor 1 of the above-described embodiment can select the signal to be output to the signal measurement output terminal 3 by software, the sampling start condition input probe used in the logic analyzer is set to the signal measurement output terminal 3. All you have to do is connect them. Also, changes in sampling conditions can be handled only by software without changing probes.

〔The invention's effect〕

As described above, according to the present invention, the signal output control register for measuring the signal to be output from the signal measurement output terminal from the input / output signals of the input / output signal terminal by software and the signal output control register are set. Since it is configured with the signal control means that outputs the signal to the signal measurement output terminal, the signal to be output to the signal measurement output terminal can be selected from the input / output signals, and the sampling start condition of the logic analyzer as in the past can be selected. Even if you had to connect multiple probes to the signal line to configure
All you have to do is to connect the two probes, and if you want to change the sampling start condition, just change the signal set in the signal output control register, reconnect the probe as before, and then start sampling. It is possible to save the trouble of changing the conditions, and thus it is possible to improve the efficiency of debugging the hardware of the microprocessor system.

[Brief description of drawings]

FIG. 1 is a block diagram of the essential parts of a microprocessor according to an embodiment of the present invention, FIG. 2 is a diagram showing the contents of a signal output control register in FIG. 1, and FIG. 3 is a conventional microprocessor system. FIG. 4 is a diagram for explaining a hardware debug environment, and FIG. 4 is a timing chart of a signal line to be measured. 1 ... Microprocessor, 2 ... Input / output signal terminal, 3
...... Signal measurement output terminal, 4 ...... Signal output control register, 5 ...... Signal output control means.

Claims (1)

(57) [Claims] 1. A signal measuring output terminal for outputting a signal to be measured, an input / output signal terminal for inputting / outputting a signal, and a signal to be output from the signal measuring output terminal, which is the input / output signal. A signal output control register that is set by software from among the input / output signals of the terminal, and signal output control means that outputs the signal set in the signal output control register to the signal measurement output terminal. A microprocessor to do.