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Switch interface (software) Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. ● You are creating the user interface for your application. Problem How do you connect the port pin of an 8051 microcontroller […]
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On–off switch Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. ● You are creating the user interface for your application. Problem How do you obtain the behaviour illustrated in Figure 19.9 from a […]
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Multi-state switch Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. ● You are creating the user interface for your application. Problem How do you obtain the behaviour illustrated in Figure 19.13 from a […]
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Keypad interface Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. ● You are creating the user interface for your application. Problem How do you connect a small keypad, similar to that illustrated in […]
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Switch interface (hardware) Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. ● You are creating the user interface for your application. Problem How do you create a very robust switch interface for use […]
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Introduction Reading the status of one or more push-button switches is a very common require- ment in embedded applications. The four patterns in this chapter describe different solutions to this problem. The patterns are as follows: ● SWITCH INTERF ACE ( SOFTW ARE ) [page 399] Uses a minimum of external hardware. Reads a single […]
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Example: An output-only library for the 8051/8052 (generic) This example again illustrates how to link a Standard 8051 device to a PC. Unlike the first example, the software is ‘write only’: data are transferred from the microcontroller to the PC but not vice versa. To illustrate this, the software displays elapsed time on the PC […]
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Pc link (rs-232) Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. ● You are creating the user interface for your application. Problem How do you link your embedded application to a desktop (or […]
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Multi–state task Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● The application has a time-triggered architecture, constructed using a scheduler. Problem How do you replace multiple tasks in an application with a single task that performs different activities depending on the current state […]
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Hardware delay Context ● You are developing an embedded application using one or more members of the 8051 family of microcontrollers. ● You are designing an appropriate software foundation for your application. Problem You need to wait for a fixed period of time (measured in milliseconds) before taking some action. Background — Solution All members […]
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