7733 datasheet(222/940 Pages) RENESAS

222 / 940 page

SERIAL I/O

7733 Group User’s Manual

8–19

(1) Interrupt priority level selection bits (bits 2 to 0)

These bits are used to select the priority level of the UARTi transmission interrupt or UARTi reception

interrupt. When using the UARTi transmission/reception interrupt, select one of priority levels 1 to 7.

When a UARTi transmission/reception interrupt request occurs, its priority level is compared with the

processor interrupt priority level (IPL) and the requested interrupt is enabled only when its priority level

is higher than the IPL. (Note that this is applied when the interrupt disable flag (I) = “0.”) When these

bits are set to “0002” (level 0), the UARTi transmission/reception interrupt is disabled.

(2) Interrupt request bit (bit 3)

The UARTi transmission interrupt request bit is set to “1” when data is transferred from the UARTi

transmission buffer register to the UARTi transmission register.

The UARTi reception interrupt request bit is set to “1” when data is transferred from the UARTi receive

occurs.

When each interrupt request is accepted, the corresponding interrupt request bit is automatically

cleared to “0.” Note that each bit can be set to “1” or cleared to “0” by software.

8.2 Block description

7733 Datasheet(PDF) 222 Page - Renesas Technology Corp