KR20050030253A - Interface device for jtag i/o test - Google Patents

Abstract

An interface device for a JTAG(Joint Test Action Group) I/O test is provided to prevent a time for connecting with a JTAG interface from increasing, without comprising another pin/test points for outputting trace data in a terminal MSM, thereby shortening a development period. A cable connector(20) includes a charging port(22), and comprises as follows. A body(21) has JTAG plugs(23) for electrically connecting with a debugging test tool on one side. A plug(25) is ejected from the body(21) by a cable, and couples 5 JTAG signal lines in connection with an interface connector of a terminal. A USB plug(26) is ejected from the body(20) by a cable, and connects with a PC through a USB port.

Description

Interface device for I / O test by international joint test action group {INTERFACE DEVICE FOR JTAG I / O TEST}

The present invention relates to a debugging test apparatus for a terminal by JTAG according to IEEE standard 1149.1-1990 or IEEE standard 1149.1-1990 (including IEEE standard 1149.1a-1993), and is particularly configured to facilitate connection between the terminal and the debugging test tool. Interface device for JTAG I / O testing.

Typically, well-known methods for testing complex integrated circuits implemented in integrated circuit (IC) chips are the IEEE 1149.1 boundary-scanned standard (JTAG) created by the International Joint Test Action Group (JTAG). to be. One implementation of this standard provides devices for serial boundary-scan testing by providing daisy chained shift-register elements to form a path that surrounds the periphery of the integrated circuit device. Designing an integrated circuit).

The general concept of serial testing using JTAG is to shift serial data into and through multiple integrated circuit devices to stimulate a circuit inside the integrated circuit device, i.e. generate certain output signals from the circuit. Then, the data generated by the integrated circuit elements or received by the input pins of the integrated circuit elements is shifted from the integrated circuit elements to the JTAG master test circuit.

If the data stream returned to the master test circuit is different from what was expected, a malfunction in the circuit is detected by the test circuit. By carefully analyzing the deviations present in the data stream under software control, any malfunctions present in the circuit can be isolated.

In the existing test method using the JTAG interface described above, five test points for the JTAG signal were made on the PBA of the RF board of the terminal and used as a jumper.

1A and 1B are diagrams of a PBA showing the location of a test point for a JTAG signal according to the prior art, which is conventionally tested by connecting an ICD cable on the PBA as shown in FIG. 1A, or as shown in FIG. 1B. The test was performed by creating test points on the screen.

However, as described above, when using a jumper on the PBA is used for a considerable time, there is an inconvenient problem that the order and position of the test point for connecting the JTAG signal for each model has to be changed.

SUMMARY OF THE INVENTION An object of the present invention is to provide an interface device for a JTAG input / output test configured to perform test preparation in a short time using a standard interface connector of a terminal.

It is another object of the present invention to provide an interface device for JTAG input / output test configured to reduce development time when applied to various models.

In order to solve the above object, the present invention provides an interface device for connecting a terminal and a debugging test tool for input / output testing by JTAG, wherein the test points for the JTAG signal line are connected to an open contact portion. A cable connector having a JTAG plug for connecting to an interface connector of the terminal to be connected to each other and the terminal interface connector on one side, the contact portion corresponding to the JTAG signal lines is formed, the other side is connected to the debugging test tool Characterized by including.

Hereinafter, with reference to the accompanying drawings will be described.

2 is a circuit diagram of an interface connector of a portable wireless terminal according to the present invention. The terminal is not shown, and only the interface connector 10 is shown. The interface connector 10 is connected to a power supply line, a USB data line, a ground terminal, and the like. In the present invention, five open lines of the interface line are used as test points for the JTAG signal, and the corresponding cable connectors are connected to the debugging test tool.

As shown in FIG. 2, the JTAG signal line includes an optional test reset signal (TRST_) 11, a test data input signal (TDI) 12, a test mode selection signal (TMS) 13, and a test clock signal (TCK). 14 and a test data output signal (TDO) 15.

3 is a schematic diagram of a cable connector 20 for electrically connecting an interface connector (10 of FIG. 2) and a debugging test tool of a terminal according to the present invention, wherein the cable connector 20 according to the present invention is charged. It includes a sphere 22, the body 21 is provided with a JTAG plug 23 for electrically connecting to the debugging test tool on one side, and drawn out by a cable of a predetermined length on the body 21, the end It is connected to the interface connector (10 in FIG. 2) of the terminal, the plug 25 for connecting the above-mentioned five JTAG signal lines (11, 12, 13, 14, 15) and a predetermined length on the body 20 It is drawn out by a predetermined cable, and the end is provided with a USB plug 26 connected to a USB port such as a PC. The plug 25 may preferably be a 24-pin plug.

4 is a circuit diagram of a cable connector according to the present invention, which shows a charging port 22 installed in a body and a JTAG plug 23. The JTAG plug 23 also includes an optional test reset signal TRST_, a test data input signal TDI, a test mode select signal TMS, a test clock signal TCK, and a test data output signal TDO. Furthermore, it has two data transmission lines, USB D + and USB D-, which are connected to the data transmission part of the connected device, and consists of a ground terminal and a vbus line for supplying power. Since it is a known USB component, it is not encoded.

FIG. 5 is a circuit diagram illustrating a cable connection structure of a cable connector according to the present invention, and shows a 24-pin connector (T24 USB cable) 25 of the cable connector 20, and shows a USB plug 26 on the lower side thereof. It is shown.

Therefore, when the terminal's MSM sends signals for the JTAG interface (TRST_, TDI, TMS, TCK, TDO) to the plug of the cable connector (T24 USB cable) connected to it through the terminal's interface connector, these signals Make it like a DSP JTAG (CON14) (21 ') to be connected. After that, the test can be performed by connecting the ICD cable to the JTAG plug protruding from the outside.

That is, the interface device for testing using the JTAG according to the present invention can output trace data using pins for 24PIN IF CONNECTOR input / output implemented in the terminal.

In addition, with the development of MSM, which is a control unit of the terminal, the number of pins may increase by adding terminals such as RTCK and RESET.

Apparently, there are many ways to modify these embodiments while remaining within the scope of the claims. In other words, there may be many other ways in which the invention may be practiced without departing from the scope of the following claims.

The MSM of the terminal using the interface device according to the present invention does not need to have separate pins / test points for outputting trace data, and increases the space on the PBA by implementing PBA with separate pins for outputting trace data. By reducing the time spent connecting the JTAG interface, the development time can be shortened, resulting in cost savings.

1A and 1B are diagrams of a PBA showing the location of a test point for a JTAG signal in accordance with the prior art;

2 is a circuit diagram of an interface connector of a portable radio terminal according to the present invention;

3 is a schematic diagram of a cable connector for electrically connecting an interface connector and a debugging test tool of a terminal according to the present invention;

4 is a circuit diagram of a body including a charging port of a cable connector according to the present invention; And

5 is a circuit diagram showing a cable connection structure of a cable connector according to the present invention.

Claims (2)

An interface device for connecting a terminal and a debugging test tool for input / output testing by JTAG, An interface connector of the terminal each having test points for the JTAG signal line connected to an open contact portion; A JTAG cable connected to the terminal interface connector at one side, the plug having a contact portion corresponding to the JTAG signal lines, and a JTAG plug for connecting to a debugging test tool at the other side; Interface device for I / O testing. The method of claim 1, The cable connector further comprises a separate USB plug interface device for JTAG input and output testing.