Title:
VFO CIRCUIT INITIAL SETTING SYSTEM
Document Type and Number:
Japanese Patent JPS61162868
Kind Code:
A
Abstract:
PURPOSE:To make initial adjustment of a VFO circuit simply by giving an adjustment mode signal to a dividing rate switching circuit, a changeover switch and a VFO circuit at the time of initial setting of the VFO circuit, dividing a write clock at a desired dividing rate and inputting to the VFO circuit. CONSTITUTION:By setting the mode to an adjustment mode by making an adjustment mode instructing signal high, a specified dividing rate is set to a frequency dividing circuit 2 by a dividing rate switching circuit 7, and the frequency of a write clock is set to a frequency necessary for adjusting the VFO circuit 6. By giving the adjustment mode instructing signal, a changeover switch 5 is changed to the contact A side, and accordingly, a write clock having frequency for adjusting is inputted to the VFO circuit 6. As a floppy disk controller 3 does not require to function when adjusting the VFO circuit 6, no problem takes place even when the frequency of the write clock is changed like this. Thus, it is possible to generate a signal for adjusting the VFO circuit very easily, and it is not necessary to provide a circuit for generating the signal for adjusting separately.
Inventors:
YAMAUCHI YOSHIHIRO
Application Number:
JP203285A
Publication Date:
July 23, 1986
Filing Date:
January 11, 1985
Export Citation:
Assignee:
RICOH KK
International Classes:
G11B20/10; H03K5/00; H03L7/00; H04L7/033; (IPC1-7): H03K5/00; H03L7/00; H04L7/02
Attorney, Agent or Firm:
Masaaki Kobashi