Bootloader是微處理器上電時(shí)運(yùn)行的第一段代碼,它可以通過通信接口實(shí)現(xiàn)對微處理器內(nèi)部應(yīng)用程序的更新升級(jí),為網(wǎng)絡(luò)化嵌入式產(chǎn)品的應(yīng)用程序升級(jí)帶來極大的便利。由于目前沒有統(tǒng)一嵌入式系統(tǒng)的Bootloader。基于NEC 78K0系列單片機(jī)自編程原理,設(shè)計(jì)出一個(gè)適用于78K0/Fx2系列單片機(jī)的Bootloader,并能夠通過單片機(jī)串口在線升級(jí)應(yīng)用程序。
Abstract:
Bootloader is the first piece of code executed after microprocessor startup. It makes the embedded product’s firmware update conveniently through communication interface. However, no unified bootloader is available for all kinds of microprocessor products. Based on the principle of self-programming NEC 78K0s’ series, a useful Bootloader which is suitable for 78K0/Fx2s’ series MCU is designed,the design can update the application through serial ports.
The CAT28LV64 is a low voltage, low power, CMOS Parallel EEPROM organized as 8K x 8−bits. It requires a simple interface for in−system programming. On−chip address and data latches, self−timed write cycle with auto−clear and VCC power up/down write protection eliminate additional timing and protection hardware. DATA Polling and Toggle status bit signal the start and end of the self−timed write cycle. Additionally, the CAT28LV64 features hardware and software write protection.
The STWD100 watchdog timer circuits are self-contained devices which prevent systemfailures that are caused by certain types of hardware errors (non-responding peripherals,bus contention, etc.) or software errors (bad code jump, code stuck in loop, etc.).The STWD100 watchdog timer has an input, WDI, and an output, WDO (see Figure 2). Theinput is used to clear the internal watchdog timer periodically within the specified timeoutperiod, twd (see Section 3: Watchdog timing). While the system is operating correctly, itperiodically toggles the watchdog input, WDI. If the system fails, the watchdog timer is notreset, a system alert is generated and the watchdog output, WDO, is asserted (seeSection 3: Watchdog timing).The STWD100 circuit also has an enable pin, EN (see Figure 2), which can enable ordisable the watchdog functionality. The EN pin is connected to the internal pull-downresistor. The device is enabled if the EN pin is left floating.
Abbrevia is a compression toolkit for Borland Delphi, C++Builder, & Kylix. It supports PKZIP 4, Microsoft CAB, TAR, & gzip formats & the creation of self-extracting archives. It includes visual components that simplify the manipulation of ZIP files.
% This program calculates radar ranges in a jamming environment. It works
% with both Stand-off jamming and self-screening jamming for steady and Swerling type
% targets with frequency agility, coherent integration and standard atmosphere/rain
% attenuation
C++ Standard Library provides a set of common classes and interfaces that greatly extend the core C++ language. The library, however, is not self-explanatory. To make full use of its components-and to benefit from their power-you need a resource that does far more than list the classes and their functions.
The C++ Standard Library not only provides comprehensive documentation of each library component, it also offers clearly written explanations of complex concepts, describes the practical programming details needed for effective use, and gives example after example of working code.