Lake Erie Systems 8900 Series, Technical Reference Manual

Page: 204 / 224

Communication Interfaces 10-13
Parallel Interface Timing Requirements (continued)
Item Ref. Timing Requirements
f Trailing edge must occur before the host
can strobe the next character into the
receive buffer. For normal write cycles
(receive buffer not full), this occurs at 10
µ
s
min., 500
µ
s nom., and 1000
µ
s max. after
the leading edge of STROBE-.
DATA1-8 g The host writes the next character to the
interface. This can occur at any time
after the data stabilization time and hold
time of the previous character have
elapsed. (See Reference items a-b and
b-c on the preceding page.)
STROBE- h The host places the next strobe pulse on
the interface to initiate the next character-
transfer operation.
Initialize Sequence
The initialize sequence is a host-generated power-up reset sequence.
When the host activates INIT-, the printer performs the following
sequence.
1. Interrupts any ongoing operation.
2. Assumes the offline state.
3. Executes the normal power-up self-test routine.
4. Returns to the online state.