C165H Datasheet, PDF (149/499 Pages) Infineon Technologies AG – EMBEDDED C166 WITH USART IOM-2 AND HDLC SUPPORT

C165H
Parallel Ports
Write ODP3.y
Open Drain
Latch
Read ODP3.y
Write DP3.y
Y ^Ι
n
t
Direction
R ^e
Latch
r
n
Read DP3.y
A ^a
l
IN ^{- B}
u
s
Write P3.y
Alternate
Data
Output
&
T _{Port Output}
IM ^Latch
P _{Read P3.y}
REL ^{CER y=13,11...5,3}
1
MUX
0
Alternate
Data
Input
P3.y
Output
Buffer
Clock
Input
Latch
MCB02229
P ^{X Figure 35 Block Diagram of a Port 3 Pin with Alternate Input or Alternate}
- ^{E Output Function (y = 13, 11...5, 3)}
Pin P3.12 (BHE/WRH) is one more pin with an alternate output function. However, its
structure is slightly different (see figure below), because after reset the BHE or WRH
function must be used depending on the system startup configuration. In these cases
there is no possibility to program any port latches before. Thus the appropriate alternate
function is selected automatically. If BHE/WRH is not used in the system, this pin can be
used for general purpose I/O by disabling the alternate function (BYTDIS = ‘1’ /
WRCFG=’0’).
Data Sheet
149
2001-04-19