r5f71374an80fpv Renesas Electronics Corporation., r5f71374an80fpv Datasheet - Page 970

• Manufacturer Part Number: r5f71374an80fpv
• Description: 32-bit Risc Microcomputer Superh?? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

Section 22 Flash Memory
22.8.2
(1) Download of On-Chip Program
(1.1) VBR setting change
(1.2) SCO download request and interrupt request
Rev. 1.00 Sep. 21, 2007 Page 944 of 1124
REJ09B0402-0100
Before downloading the on-chip program, VBR must be set to H'84000000. If VBR is set to a
value other than H'84000000, the interrupt vector table is placed in the user MAT (FMATS is
not H'AA) or the user boot MAT (FMATS is H'AA) on setting H'84000000 to VBR.
When VBR setting change conflicts with interrupt occurrence, whether the vector table before
or after VBR is changed is referenced may cause an error.
Therefore, for cases where VBR setting change may conflict with interrupt occurrence, prepare
a vector table to be referenced when VBR is H'00000000 (initial value) at the start of the user
MAT or user boot MAT.
Download of the on-chip programming/erasing program that is initiated by setting the SCO bit
in FCCS to 1 generates a particular interrupt processing accompanied by MAT switchover.
Operation when the SCO download request and interrupt request conflicts is described below.
1. Contention between SCO download request and interrupt request
Figure 22.21 shows the timing of contention between execution of the instruction that sets
the SCO bit in FCCS to 1 and interrupt acceptance.
Interrupts during Programming/Erasing
Figure 22.20 Switching between User MAT and User Boot MAT
<User MAT>
Procedure for switching to the user boot MAT
(1) Mask interrupts.
(2) Write H'AA to FMATS.
(3) Execute four NOP instructions before
Procedure for switching to the user MAT
(1) Mask interrupts.
(2) Write a value other than H'AA to FMATS.
(3) Execute four NOP instructions before accessing
accessing the user boot MAT.
the user MAT.
<On-chip RAM>
switching to the
user boot MAT
Procedure for
Procedure for
the user MAT
switching to
<User boot MAT>