h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 707

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

input to the FWE pin, and H'00 when a low level is input. When on-chip flash memory is disabled,
a read will return H'00, and writes are invalid.
Writes are enabled only in the following cases: Writes to bit SWE of FLMCR1 enabled when
FWE = 1, to bits ESU, PSU, EV, and PV when FWE = 1 and SWE = 1, to bit E when FWE = 1,
SWE = 1 and ESU = 1, and to bit P when FWE = 1, SWE = 1, and PSU = 1.
Bit 7—Flash Write Enable Bit (FWE): Sets hardware protection against flash memory
programming/erasing.
Bit 6—Software Write Enable Bit (SWE): Enables or disables flash memory programming and
erasing. Set this bit when setting bits 5 to 0, bits 7 to 0 of EBR1, and bits 1 and 0 of EBR2.
Bit 5—Erase Setup Bit (ESU): Prepares for a transition to erase mode. Set this bit to 1 before
setting the E bit in FLMCR1 to 1. Do not set the SWE, PSU, EV, PV, E, or P bit at the same time.
Bit 4—Program Setup Bit (PSU): Prepares for a transition to program mode. Set this bit to 1
before setting the P bit in FLMCR1 to 1. Do not set the SWE, ESU, EV, PV, E, or P bit at the
same time.
Bit 7
FWE
0
1
Bit 6
SWE
0
1
Bit 5
ESU
0
1
Description
When a low level is input to the FWE pin (hardware-protected state)
When a high level is input to the FWE pin
Description
Writes disabled
Writes enabled
[Setting condition]
When FWE = 1
Description
Erase setup cleared
Erase setup
[Setting condition]
When FWE = 1 and SWE = 1
Rev. 5.00 Sep 22, 2005 page 681 of 1136
REJ09B0257-0500
Section 20 ROM
(Initial value)
(Initial value)