|
The DF-224 is a space-qualified computer used in space missions from the 1980s. It was built by Rockwell Autonetics. As with many spacecraft computers, the design is very redundant, since servicing in space is at best difficult and often impossible. The configuration had three CPUs, one active and two spares. The main memory consisted of six memory units, each with 8K 24-bit words of plated wire memory, with up to 48K words total. Four memory modules could be powered up at one time, resulting in a maximum of 32K words of available memory, though some applications such as the Hubble Space Telescope used fewer memory banks to allow for graceful failure modes.〔(【引用サイトリンク】title=DF-224/Coprocessor )〕 There were three IO processors, one operational and two backups. The power supply consisted of 6 independent power converters, with overlapping coverage of the operating functions. The processor used fixed-point arithmetic with a two's complement format. By the standards of 2010, the computer was rather big and slow. It was roughly by by , weighed , and had a clock speed of 1.25 MHz.〔 (Page 499 )〕 According to a Hubble servicing mission report, when the DF-224 was replaced by a 25 MHz Intel i486, processing power increased about 20x.〔 Section 1-7.〕 ==See also== *IBM RAD6000 - a more modern space-qualified computer. *RAD750 - newer version *Mongoose-V - radiation hard processor based on the MIPS-3000. *Various implementations of the MIL-STD-1750A 16-bit processor have been used in several spacecraft 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「DF-224」の詳細全文を読む スポンサード リンク
|