Mos Pull-Up Transistors - Hitachi H8S/2199 Hardware Manual

10.1.3

MOS Pull-Up Transistors

The MOS pull-up transistors in ports 1 to 3 can be switched on or off by the MOS pull-up select
registers 1 to 3 (PUR1 to PUR3) in units of bits. Settings in PUR1 to PUR3 are valid when the pin
function is set to an input by PCR1 to PCR3. If the pin function is set to an output, the MOS pull-
up transistor is turned off. Figure 10.1 shows the circuit configuration of a pin with a MOS pull-
up transistor.
Legend
LPWRM
PUR
PCR
PDR
Figure 10.1 Circuit Configuration of Pin with MOS Pull-Up Transistor
Rev. 1.0, 02/00, page 188 of 1141
V V
CC CC
V
SS
: Low power consumption mode signal
(The pull-up MOS transistor is turned off by the STBY signal in low power
consumption mode except for sleep mode)
: MOS pull-up select register
: Port control register
: Port data register
STBY
PUR
PCR
PDR
Input data