However , because of the low speed of program operation and the invalid blocks of flash memory , if we want to make it the storage medium of solid state recorder on the spacecraft , several problems need to be resolved : 1 ) how to improve the speed of program and erase operation of flash memory ; 2 ) how to map out and bypass the invalid blocks and effectively manage the mass memory space 但是由于flash的写入(编程)速度慢、存在无效块等问题,使要将其应用于星载大容量存储器,亟待解决以下几个问题: ( 1 )如何有效地提高闪存的编程和擦除速度; ( 2 )如何标识和旁路初始和使用过程中出现的无效块,并有效地管理大容量数据存储器。
Pipelining and parallel technology , accompanying with fast fifo as cache memory , instead of direct program operation , are adopted in the scheme and increase the transmitting speed dramatically ; fpga ( field programmable gate array ) is applied to realize the complex control logic of the system and makes it integrative , flexible and fast ; 386ex based embedded system , along with vxworks real - time operating system is introduced to substitute the microcontroller based system to simplify the hardware design and enhance the overall performance of ssr , and will make the system more easier to be applied to the projects in the future 该设计方案采用了流水线和并行技术,配以快速fifo缓存的方式取代了直接对flash进行编程的方式,极大地提高了闪存芯片存储数据的速率;采用fpga技术实现系统的主要控制逻辑,集成度高、灵活性好、速度快;采用基于386ex的嵌入式系统及基于vxworks的嵌入式实时操作系统,取代单片机系统及其编程,提高了系统的整体性能,减轻了硬件设计的负担,且使系统研发的延续性好。
This board member for originally can develop each significant project in the implementation and conduct each kind of international large - scale activity , and this meets the overall development program operation , in order to accelerate to achieve this meeting grand goal , and this meets the overall development program operation , in order to accelerate to achieve this meeting grand goal , soon will realize for the world society ' s honored enterprise and great benefits the world international society to offer the compassion , great project victory implementation service 该委员会委员为本会在实施开展各项重大项目和举办各种国际大型活动,及本会总体发展方案运作,为加速实现本会的宏伟目标,早日实现为世界社会的光彩事业和伟大的造福世界国际社会献爱心,伟大工程胜利实施服务。
The paper has begun with existing driving mechanism of horizontal barrel finishing equipment and analysed the reason that creates the family of crank parts machining quality problem . the transmission plan of noncircular gears connect crank - slider mechanism has been presented and mathematical model of driving mechanism has been established . by way of programming operation , simulation analysis and parameter optimization , the feasibility of new plan has been proofed 本课题从现有卧式滚磨设备的传动机构入手,对造成曲轴类零件加工质量问题的原因进行了分析,提出引入非圆齿轮串联曲柄滑块机构的传动方案,建立了传动机构的数学模型,通过计算机编程运算及模拟分析和参数优化,验证了所提新方案是可行的。