IBM 1 Series Manual page 42

Cycle steal request in or
request in bus of capturing
Channel time-out
device (leading poll ID)
Cycle steal
request in or
request in bus
of capturing
device __ x
(lagging poll ID)*
Poll identifier
Poll
CT1
CT4
Burst return
T3
TS
Service sequences
CT3
Last transfer service gate return
* = cycle steal request in or request in bus of capturing
device is lagging poll ID and did not causepoll ID.
Timings:
Ti < 100 ns (T1 maybe negative)
T2 < T3 < 100 ns
T4 > 100 ns
TS > 0
CT1 > 180 ns
CT2 2 0
CT3 > 0
CT4 > 100 ns
CTS >0
Figure 2-12. Poll sequence with 'burst return' timing diagram
Key:
CT = channel times.
T
= attachment controlled times.