Welcome to the training module on S08SF 8 Bit Microcontrollers and Development Kits.
This training module will introduce S08SF 8 Bit Microcontroller, its key features, the demonstration board as well as sample application
Freescale is a leading supplier of embedded controllers with a strong legacy in the industrial market. The high-performance 8-bit technology offers designers more cost-effective design choices for all kinds of applications. This high performance core is optimized for extreme economy and boasts several low power options which makes it very attractive for battery-powered and hand-held applications. Multiple Stop modes, along with Wait and Standby modes, will help product developers achieve new thresholds in low-power performance under a variety of operating conditions.
The 8-bit MC9S08SF4 MCU family is optimized to provide precise, quiet and safe control for simple motor control applications. An integrated, advanced set of features, including six timers and up to 18 general purpose input/output (GPIO) pins, provides highly accurate control and helps simplify overall system design. An enhanced protection circuit design and a wide operating temperature range of -40 º C to +125 º C helpsth system to be operated safely and reliably under variable conditions.
This is the simplified block diagram of the MC9S08SF4 MCUs. Based on Freescale’s proven S08 architecture, the device operates at up to 40MHz CPU speed from 2.7V to 5.5V. Its 4 kilo bytes of Flash memory support read, program and erase modes across the full voltage and temperature range, allowing in-application reprogramming in virtually any environment. A focused set of integrated modules addresses control challenges specific to DC motors. These include a 2.5μs, 8-channel, 10-bit ADC, as well as six timers including two 40MHz timer/PWM modules for precision control and low noise. There are also two 16-bit modulo timers and two 16-bit pulse-width timers supporting fast, accurate sensing and control. In addition, two 5-bit programmable reference analogue comparators enhance the response to analogue signals. For interrupt intensive applications, an Interrupt-Priority Controller (IPC) supports up to 32 extra interrupt sources in addition to the CPU’s interrupt table.
The interrupt priority controller (IPC) provides hardware based nested interrupt mechanism to simplify software design. The IPC works with the existing HCS08 interrupt mechanism to allow nestable interrupts with programmable priority levels. This module also allows implementation of preemptive interrupt according to the programmed interrupt priority with minimal software overhead. The IPC supports up to 32 extra interrupt sources in addition to the CPU’s interrupt table.
The system protection features of the S08SF MCUs, including the COP Watchdog timer, the low-voltage detection system, ILOP and ILAD detection, and flash memory protection features. The COP timer allows the CPU to recover to a known, fixed state after some sort of unexpected event occurs. The COP timer also allows you to select the time-out period and the length of the time-out period. The COP timer resets the microcontroller if it is not cleared manually by the user software within the time-out period. The low-voltage detection system help secure data and warn of possible voltage loss conditions. The low-voltage detection circuitry is very useful in battery-type applications and applications where the supply voltage may be unexpectedly interrupted or unexpectedly decay. The ILOP allows the device to recognize erroneous code and to reset the processor to help avoid lock. And the ILAD resets the MCU to a known state following inadvertent access. The flash block protection settings are actually loaded at reset and they cannot be modified by user code. It provides security by protecting code from unauthorized or unintentional access.
Development support systems in the S08SF include the background debug controller (BDC) and the on-chip debug module (DBG). The BDC provides a single-wire debug interface for the target MCU that provides a convenient interface for programming the on-chip FLASH and other nonvolatile memories. The BDC is also the primary debug interface for development. It allows non-intrusive access to memory data and traditional debug features such as CPU register modify, breakpoints, and single instruction trace commands.
The DEMO9S08SF4 is a demonstration board for the MC9S08SF4 microcontroller. The board is a cost-effective kit, targeting quick MC9S08SF4 evaluation. It can be used to demonstrate the features of the MC9S08SF4 devices. Application development is quick and easy with the integrated, Open-Source, USB-BDM, sample software tools, and examples. An optional BDM_PORT port is also provided to allow use of a BDM_PORT cable. One, 40-pin connector provides access to all IO signals on the target MCU.
The DEMO9S08SF4 board features an integrated Open Source BDM (USB-BDM) based on the Freescale MC9S08JM60 MCU. The integrated USB BDM supports application development and debugging via background debug mode and provides primary power to the development module. The integrated USB BDM provides power and ground to the target board eliminating the need to power the board externally. The RESET switch applies an asynchronous RESET to the MCU. The RESET switch is connected directly to the RESET input on the MCU. Two push button SW1 and SW2 switches provide momentary, active-low input, for user applications. An externally modulated piezo-buzzer, with a center frequency of 2300 Hz for audible applications is applied. A 5k ohm, thumb-wheel type, potentiometer at RV1 is used as a voltage divider that changes as the thumb-wheel is turned.
The stator and rotor windings of the motor are connected in series through the rotor commutator. Therefore the universal motor is also known as an AC series motor or an AC commutator motor. The universal motor can be controlled either as a phase-angle drive or as a chopper drive. The S08SF 8-bit MCUs offer lowest cost and power solutions. It has dedicated motor control peripherals, high energy efficiency and extensive motor control library. Both features provide precise, quiet and safe control for simple motor control applications.
Thank you for taking the time to view this presentation on “ S08SF 8 Bit Microcontrollers and Development Kits ” . If you would like to learn more or go on to purchase some of these devices, you may either click on the part list link right beside the play button on the TechCast portal, or simply call our sales hotline. For more technical information you may either visit the Freescale site, or if you would prefer to speak to someone live, please call our hotline number, or even use our ‘live chat’ online facility. You may visit element14 e-community to post your questions.