User's Manual

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 324 of 1852
Nov 30, 2020
RX23W Group 16. Buses
16.4.2 Operations When a Bus Error Occurs
When a bus error occurs, the error is indicated to the CPU. Operation is not guaranteed when a bus error occurs.
Bus error indication to the CPU
An interrupt is generated. The IERn register in the ICU can specify whether to generate an interrupt in the case of a
bus error.
16.4.3 Conditions Leading to Bus Errors
Table 16.5 lists the types of bus errors for each area in the respective address space.
If an illegal address access error or timeout is detected when no bus error has occurred (bus error status register n
(BERSRn; n = 1 or 2) is cleared), the detected error is reflected on the BERSRn. Once a bus error occurs, no subsequent
bus errors are reflected on the register unless the register is cleared.
If bus errors are simultaneously caused by two or more bus masters, error information of only one bus master is reflected.
Once a bus error occurs, the status is retained until BERSRn is cleared.
—: A bus error does not result.
Δ: A bus error may or may not result.
: A bus error results.
Note: The capacity of the RAM, E2 DataFlash, and ROM differs depending on the product. For details, see section 49, RAM, section
50, Flash Memory (FLASH).
Table 16.5 Types of Bus Errors
Address Type of Area
Type of Error
Illegal Address Access Timeout
0000 0000h to 0007 FFFFh Memory bus 1
0008 0000h to 0008 7FFFh Internal peripheral bus 1
0008 8000h to 0009 FFFFh Internal peripheral bus 2
Δ
000A 0000h to 000B FFFFh Internal peripheral bus 3
Δ
000C 0000h to 000D FFFFh Internal peripheral bus 4
Δ
000E 0000h to 000F FFFFh Reserved area
0010 0000h to 0011 FFFFh Internal peripheral bus 6
0012 0000h to 007F FFFFh
Δ
0080 0000h to 00FF FFFFh
0100 0000h to 07FF FFFFh Reserved area
0800 0000h to 0FFF FFFFh
1000 0000h to 7FFF FFFFh
8000 0000h to FEFF FFFFh Memory bus 2
FF00 0000h to FF7F FFFFh
FF80 0000h to FFFF FFFFh