Mitel DISTRIBUTED HYPERCHANNEL MT90840 - Manual (Page 41)

Preliminary Information
MT90840
2-271
Figure 25 - Timing for the Parallel Port External Control Lines CTo0-3
Figure 26 - TM1 Parallel Port Transmit Timing (TM1 & PFDI = 1, PPFT is an input)
Figure 27 - Parallel Port Transmit Timing (PFDI = 0, PPFT is an output)
PDo0-7
CTo0-3
PCKT/PCKR TCP controls the clock-edge
on which the output changes.
byte m-1 byte m byte m+1
TCP = 1
PDo0-7
CTo0-3
byte m-1 byte m byte m+1
CTo corresponding to
byte m
CTo corresponding to
byte m+1
PCKT/PCKR
t
cdf TCP = 0
t
cdf
CTo corresponding to
byte m
CTo corresponding to
byte m+1
byte 0
t
sod
PDo0-7 byte 1
t
PPFH
PCKT
PPFTi (PPFP=1)
t
az
t
clkh
t
clk
t
clkl
t
za
t
PPFS
tristate tristate
byte n
n = 2429, 2047, or 809
byte 0
t
sod
PDo0-7
byte n byte 1
t
df
t
df
PCKT/PCKR
PPFTo (PPFP=1)
t
df
t
df
Note: The depicted output timing occurs when TCP = 0. If TCP = 1, the byte at PDo0-7 port and the PPFT line will be
output on the falling edge of the PCKT/PCKR clock.
t
az
t
za
t
clkh
t
clk
t
clkl
tristate tristate
PPFTo (PPFP=0)