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1 S08 Highlighted Features

2 Why Do I Need a Slave LIN Interface Controller (SLIC)? Design Challenges Slave synchronization Slave synchronizing to LIN messaging requires a cost versus resource trade-off. Your choices are to either use an expensive crystal or another means of synchronizing that will take up timer channels CPU resources, or software to measure and adjust to the synchronization data. Portability In many traditional designs, bit-rates are pre-programmed, which locks you into a specific speed and doesn t offer simple portability to different speed networks. So, simple plug n play becomes re-program plug n play. Speed SLIC can cost effectively perform in-line factory programming when you are limited to 20 kbps. CPU resources Handling messages one byte at a time requires many interrupts, and these interrupts have a sizeable impact on performance, leaving little CPU resources for the application. Software requirements It is a requirement to support LIN error detection, ti checksums and other activities. iti This can take significant ifi amounts of software, with the development, debug and maintenance costs associated with that. With more software also comes the need for more memory on a device to hold that software, thus increasing device costs. SLIC is a hardware module used as an alternative to LIN/J2602 Slave software message processing. SLIC helps increase performance True auto-synchronization and auto-bauding find LIN frames and automatically adjust the baud rate without CPU intervention. SLIC reduces interrupt processing up to 83 percent over UART solutions with only two interrupts for any message. SLIC also eliminates many steps normally required by UART solutions (trim oscillator, detect break, measure sync signal, adjust baud rate, calculate and verify checksum, handle individual data bytes, detect errors and more). SLIC helps reduce development time Minimized driver code translates into shortened debug and development time, which enables you to use your engineering time to debug the application rather than LIN communication. SLIC helps reduce cost Uses only one software driver to handle any LIN speed on any LIN bus. This allows significant code reuse for many applications, regardless of LIN bus speed. No reprogramming is required to change bus speeds, which equates to fewer part numbers to track and stock. High-speed (up to 120 Kbps) end-of-line programming through LIN allows faster module manufacturing times and field re-programmability. Smaller driver code means less flash is required for LIN communication, resulting in more flash available to use for product applications. SLIC does not require oscillator trimming, unlike UART, which simplifies the design. For more information about SLIC and its implementation, please take our online training class. 1

3 Why Do I Need an Internal Clock Source (ICS)? Design D i Challenges Eliminate use of external clock source Crystal/resonator cost Board space Wait time to startup wastes power Need clock that can handle harsh environment involving shock Self-contained clock onboard, eliminates external crystal Within 2% accuracy Provides accurate on-chip clock source Saves cost by eliminating the need for external components. Quick start up with no time delay Power savings because wake up from stop allows you to be up and running immediately, lowering overall current Robust, not effected by shock, so suitable for harsh environments Accuracy is suitable for many applications (e.g., SCI) Crystal/resonator can be used in addition to internal source 2

4 Why Do I Need Multi-Purpose Clock Generator? Design D i Challenges CAN requires a precise clock Low cost FLL solutions, such as ICS, don t provide the degree of accuracy needed for CAN MCG has three modes of operation: Phase-Locked Loop (PLL) Frequency-Locked Loop (FLL) Oscillator On-Chip (OSC) Provides flexibility for improved system performance and accuracy using various clock sources Includes PLL, which offers less jitter than ICS Possibly allows you to operate CAN without needing a high-frequency crystal 3

5 Design D i Challenges Multiple analog inputs System complexity Cost reduction Why Do I Need an Analog Comparator (ACMP)? Two input comparator or single input with internal reference Interrupt capability Output pin capability ADC function can be built with comparator if none exists Reduces need for ADC channels Reduces complexity for analog comparison functions performed by ADC Simplifies analog triggering 4

6 Design D i Challenges Eliminate high cost of external emulator Requires many pins Need for sophisticated debug tools Ability to debug in tight spaces Why Do I Need In-Circuit Emulation (ICE)? On-Chip, In-Circuit Emulation (ICE) permits real-time emulation of microcontroller functions at full operating voltage and frequency range without the limitations of traditional emulators Includes on-chip trigger and trace capability Eliminates expensive external emulator box and interconnect Reduces development time as emulation can be done real-time and on-chip Can be used in the target application at full speed with all the target components being used Eliminates timing, loading and drive issues Capture buffer and logic are the same as the target MCU, so no marginal timing Emulation can be performed on devices in tight spaces 5

7 Why Do I Need Background Debug Mode (BDM)? Design Challenges Ability to program the flash memory after PCB is assembled In-system debug access Read and write memory while application is running Ability to stop execution, set break points, and trace instructions Read and write CPU registers Perform calibration and field upgrades Each new controller requires different debug equipment Standardized single wire interface that is being used for all S08s, S12s, S12Xs and ColdFire V1s Used to read and write memory locations, program Flash, setup break points and control debug session On-chip debug reduces development time since changes can be made onboard and in real-time Standardization across product lines eliminates re-learning Don t have to give up application pins to perform debug, since it only uses one pin Doesn t interfere with normal use of part Don t have to buy special devices for each new controller you buy 6

8 Devices with Highlighted Features 7