AN2848 Freescale Semiconductor / Motorola, AN2848 Datasheet
AN2848
Related parts for AN2848
AN2848 Summary of contents
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... Freescale Semiconductor, Inc., 2004. All rights reserved. Rev. 0, 09/2004 Table of Contents 1 Overview .............................................................2 2 Architecture .........................................................2 3 Function Design – Hardware ..............................6 4 Function Development – Tools ...........................7 5 Function Design – Software ................................8 6 Host Interface Design ........................................11 7 Simulating the eTPU Function ..........................12 8 Summary ...........................................................12 AN2848 ...
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... TPU, which has enjoyed one of the longest successes of any microcontroller peripheral. Despite its popularity in specific markets, widespread adoption of the TPU was hindered by a lack of high-level language support and limited availability of development tools. The eTPU was designed from the start to be supported by a high-level language compiler, and as such has become accessible to and adopted by a very wide range of customers even before the silicon had been qualified ...
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The input/output channels of the eTPU each have a pair of Match and Capture units interfaced to one of two timer/counter (TCR) registers. Logic in the channel enables the hardware to detect or drive pin transitions with a high degree ...
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Architecture The hardware associated with each channel is controlled by a number of registers, which determine actions associated with the input and output pins and eTPU service requests. These registers are accessed by a special purpose eTPU engine that can ...
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Let’s look at how this architecture works by considering a classic example; see a Pulse Width Modulated (PWM) output signal on one of the channel pins, he would need a TCR and comparator to cause the output to transition high ...
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Function Design – Hardware systems implemented. Along the way, a number of difficult problems posed by the unique nature of the eTPU have been discovered and solved. This application note contains some of the wisdom of prior experience for the ...
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... The compiler passes information to the host processor allowing a one-step make process, effectively linking the eTPU functions to the host code. The information passing is enabled through a number of post-processing macros available in the Byte Craft compiler. Details of these macros will be described in a future application note. Freescale Semiconductor Programming the eTPU, Rev. 0 Function Development – Tools 7 ...
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Function Design – Software • The host compiler and linker do not require special features to use the eTPU information. Information is provided in C compatible files and the subsequent compilation of the host project can provide all the information ...
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There are three hard limits on the eTPU execution engine: program space, data store, and time. There are methods to trade off between these three, and the strategy must be dictated by the particular system design. However, there is nothing ...
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Function Design – Software • The Applications Programmers Interface (API) needs to be designed as part of the eTPU function. An eTPU function cannot be considered complete without the means to initialize and exchange data with the host. Remember that ...
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Optimize your source. The compiler has a sophisticated system of optimizers, but it cannot always rewrite inefficiently written code. We will try to provide specific examples of this in a separate application note. The design of an eTPU function ...
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Simulating the eTPU Function • Issue an initialization Host Service Request (HSR) to the channel. Note that a service request is necessary for an eTPU function thread to execute. No eTPU operation can occur until at least one HSR is ...
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THIS PAGE INTENTIONALLY LEFT BLANK Freescale Semiconductor Programming the eTPU, Rev ...
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THIS PAGE INTENTIONALLY LEFT BLANK 14 Programming the eTPU, Rev. 0 Freescale Semiconductor ...
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THIS PAGE INTENTIONALLY LEFT BLANK Freescale Semiconductor Programming the eTPU, Rev ...
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... Freescale Semiconductor was negligent regarding the design or manufacture of the part. Freescale™ and the Freescale logo are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners.© Freescale Semiconductor, Inc. 2004. All rights reserved. AN2848 Rev. 0 09/2004 ...