DS07-16301-4E Datasheet, PDF (36/99 Pages) Fujitsu Component Limited. – 32-bit RISC Microcontroller CMOS FR30 Series

MB91101/MB91101A
s PERIPHERAL RESOURCES
1. I/O Ports
There are 2 types of I/O port register structure; port data register (PDR0 to PDRF) and data direction register
(DDR0 to DDRF), where bits PDR0 to PDRF and bits DDR0 to DDRF corresponds respectively. Each bit on
the register corresponds to an external pin. In port registers input/output register of the port configures input/
output function of the port, while corresponding bit (pin) configures input/output function in data direction regis-
ters. Bit “0” specifies input and “1” specifies output.
• For input (DDR = “0”) setting;
PDR reading operation: reads level of corresponding external pin.
PDR writing operation: writes set value to PDR.
• For output (DDR = “1”) setting;
PDR reading operation: reads PDR value.
PDR writing operation: outputs PDR value to corresponding external pin.
• Block diagram
Resource input
0
1
PDR read
0
Pin
PDR
(Port data register)
Resource output 1
DDR
(Data direction register)
Resource output enable
36