公开(公告)号：US3571806A

公开(公告)日：1971-03-23

申请号：US3571806D

申请日：1969-01-14

Applicant: IBM

Inventor： MAKIE DAVID ,  MALLAR EUGENE E JR ,  STEEN ROBERT F

IPC: H04L13/06 ,  G06F13/00 ,  G06F13/38 ,  H04L7/00 ,  H04L25/50

CPC classification number: G06F13/385

Abstract: A line adapter for data transmission systems is provided with a pair of oscillators for enabling reception of signals at two different rates. An initial synchronizing character is analyzed to determine the number of voltage transitions during the period needed for transmission of the character at the higher transmission rate. If the number of transitions counted does not correspond with the number of voltage transitions in the character, a shift is made to a lower speed oscillator for data reception at the slower rate.