R01UH0822EJ0100 Rev.1.00
Page 77 of 1041
Jul 31, 2019
RX13T Group
3. Operating Modes
3.3
Details of Operating Modes
3.3.1
Single-Chip Mode
In this mode, all I/O ports can be used as general input/output ports, peripheral function input/output, or interrupt input
pins.
The chip starts up in single-chip mode if the high level is on the MD pin on release from the reset state.
3.3.2
Boot Mode
In this mode, the on-chip flash memory modifying program (boot program) stored in a dedicated area within the MCU
operates. The on-chip flash memory (ROM) can be modified from outside the MCU by using a universal asynchronous
receiver/transmitter (SCI1). For details, see
section 31, Flash Memory (FLASH)
.
When a reset is released while the MD pin is low, boot mode is selected.
3.3.2.1
Boot Mode (SCI)
When a reset is released while the MD pin is low, boot mode (SCI) is selected. For details on boot mode (SCI), refer to