Interfaces
8-16
Table 8-2 shows all protocol timings in nanoseconds.
Fastbytes Protocol Data Transfer Sequence
Your printer is equipped with Fastbytes protocol, which is an enhanced parallel
interface protocol. Fastbytes protocol may give you a faster data transfer time on some
personal computers and operating systems. Fastbytes protocol is the printer default.
If you have data transmission problems between your personal computer and the
printer, change the parallel protocol to Standard. This causes the printer to operate in
IEEE-compliant compatibility mode.
The following illustration shows the typical timing sequence.
Table 8-2: Typical Parallel Interface Timings
Time
Name
Minimum/Maximum
A
Data setup to STROBE* low
500 min.
B
STROBE* width
500 min.
C
Data hold after STROBE*
500 min.
D
STROBE* low to BUSY high
500 max.
E
ACKNLG* low until ACKNLG* high
500 min.
F
ACKNLG* high to BUSY low
1
—
G
BUSY low and ACKNLG* high to STROBE* low
500 min.
1
Relationship of ACKNLG* and BUSY is not consistent
DATA 1-8
STROBE*
ACK*
BUSY