Timing of R/W line on 68K busgreenspun.com : LUSENET : ece342 : One Thread
The timing of the R/W line was not explicitly shown in the lab handout. It is asserted along with /AS and held for the duration of the transaction - basically until /AS gets de-asserted. Thus for a write it would look just like /AS, for a read it would be the opposite of /AS.
-- Robin Grindley (email@example.com), January 24, 1999