[comp.sys.apple] VBLClock

reeder@reed.UUCP (Doug Reeder) (10/17/89)

I just found out that VBL must be polled on IIe's (i.e. it is not available
as an interruput).  This means my VBLClock will not work on IIe's.  This also
means funny screen splitting (lores/hires, text on top/graphics on bottom,
text and graphics superimposed, etc.) must read the floating bus to figure 
out when to switch, which makes it difficult to do anything else at the same
time.
-- 
Doug Reeder                          USENET: ...!tektronix!reed!reeder
Box 722 Reed College                 BITNET: reeder@reed.BITNET
Portland, OR 97202                from ARPA: tektronix!reed!reeder@berkeley.EDU
(503) 777-1551                  "A blaster can point two ways."  -Salvor Hardin