Hitachi, Ltd.

Rika Oue

Mitsuru Watabe

Shigeki Morinaga

Kunio Miyashita

Sanshiro Obara

Hiroshi Nagase

Nobuyoshi Mutoh

Yasuyuki Sugiura

Hiroshi Sugai

Sumio Kobayashi

A pulse generating device according to the present invention is operated in accordance with a pulse control command including output time data about output pulse given from external equipment such as a CPU. The pulse control command including the output time data about the output pulses is transferred to a master memory of a contents addressable memory at an optional timing from outside. The contents of that master memory are copied to a slave memory in response to copy enable signals transmitted from a copy enable device. The copy enable signals are transmitted whenever a predetermined number synchronizing signals showing an end of the pulse period are generated from the interval timer. The contents addressable memory reads out the output control command of the output pulse from a slave memory when the timer value of the interval timer coincides with the time data of the slave memory. The output control circuit transmits output pulses which correspond to the control command read out as described above. As a result, if the output time data is reloaded at an optional timing from outside, the generation of an error in the pulse width of the output pulse can be prevented. Furthermore, the load of the CPU can be reduced.

Generation of width modulated pulses by relatively adjusting rising and

Sine wave signals generated from a position detector are used as analog values to detect a fine position of a rotating or moving body, a rise or fall edge of the sine wave signal is used to detect a coarse position of the rotating or moving body, and the position or speed of the rotating or moving body is detected based on a signal indicative of the detected coarse position when the rotating or moving body is at high speed and based on a signal indicative of the detected fine position when the rotating or moving body is at low speed to thereby provide optimal control from high speed to low speed. Especially at extremely low driving, speed detection with superhigh resolution is effected using the analog value to decrease an uneven rotation of the rotating body.

Method and apparatus for detecting positions and/or speed of a moving

Growing community of inventors

Mito, Japan

Rika Oue