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ST7 SERIAL TEST CONTROLLER PROGRAMMING

2 SERIAL TEST CONTROLLER PROGRAMMING

2.1 ADVANTAGES

The advantages of STCP are numerous:

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Time to market

To reduce manufacturing cycle times, a user board can be designed to be generic,

supporting several functions. These functions can be enabled or disabled by software

according to customer requirements. In this case, STCP allows application boards to be

manufactured in one shot and programmed with different functions according to customer

needs and orders.

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Cost reduction

Software updates may be necessary in some cases because of a bug correction or a newly

implemented feature. The STCP is a flexible and painless way of performing such

modifications and at a lower cost. There is no need to add any sockets to the board or to

unsolder and change components in order to upgrade the application.

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Security

Because STCP offers an easy way to customise the user’s program, or part of it, it can be

used to insert different key codes for each board. This could be used, for example, in a door

lock system.

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Flexibility

For example, STCP can be used to allow calibration procedures to be performed directly in

the field.

2.2 USER BOARD SPECIFICATION

The user has to design his layout in order to support two modes: programming mode and user

mode.

Figure 1. shows the user board divided into two blocks:

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Block 1:

Includes all the components that play a role during programming mode:

– Connector J1, which links the user board to the programming tool.

– The ST72 MCU, which is the device to be programmed.

– Jumpers W1 to Wn, whose purpose is to isolate the pins used for programming the ST72

from the other components in Block 2. In some application configurations, isolation resis-

tors (47 k

Ω) can be used instead of jumpers.

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Block 2:

This block consists of all the other components soldered on the user board.

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