Pin Functions - Renesas Hitachi H8S/2194 Series Hardware Manual

(4) MOS Pull-Up Select Register 3 (PUR3)
7
Bit :
PUR37
Initial value :
0
R/W :
R/W
MOS pull-up selector register 3 (PUR3) controls the ON and OFF of the MOS pull-up transistor
of port 3. Only the pin whose corresponding bit of PCR3 was set to 0 (input) becomes valid. If
the corresponding bit of PCR3 is set to 1 (output), the corresponding bit of PUR3 becomes
invalid and the MOS pull-up transistor is turned off.
PUR3 is an 8-bit read/write enable register. When reset, PUR3 is initialized to H'00.
Bit n
PCR3n Description
0 The P3n pin has no MOS pull-up transistor
1 The P3n pin has a MOS pull-up transistor
11.5.3

Pin Functions

This section describes the port 3 pin functions and their selection methods.
(1) P37/TMO
P37/TMO is switched as shown below according to the PMR37 bit in PMR3 and the PCR37
bit in PCR3.
PMR37 PCR37
0 0
1
1
*
Note: * Don't care.
Rev. 2.0, 11/00, page 258 of 1037
6 5
PUR36 PUR35 PUR34
0 0
R/W R/W
Pin Function
P37 input pin
P37 output pin
TMO output pin
4 3
PUR33 PUR32
0 0
R/W R/W R/W
2 1 0
PUR31 PUR30
0 0 0
R/W R/W
(Initial value)
(n = 7 to 0)