INPUT/OUTPUT PORTS AND PIN FUNCTIONS
8.3 Input/Output Port Related Registers
8
(1) To know whether XIN oscillation has ever stopped after being reset
Read XSTAT
(2) To know the current status of XIN oscillation
Write XSTAT = 0
Wait before inspecting XSTAT
Wait for 20 CPU
clock periods or more
Read XSTAT
Figure 8.3.1 Procedure for Setting XSTAT
(2) PISEL (Port input data select) bit (Bit 14)
When the Port Direction Register is set for output, this bit selects the target data to be read from the Port Data
Register. This bit is unaffected by the Port Operation Mode Register.
Table 8.3.1 PISEL Bit Settings and the Target Data To Be Read from the Port Data Register
Direction Register
0 (input)
PISEL Settings
0/1
Target Data to Be Read
Port pin level
1 (output)
0
1
Port output latch
Port pin level
32180 Group User’s Manual (Rev.1.0)
8-22
RENESAS [ RENESAS TECHNOLOGY CORP ]
