h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 693

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Bit 3—Flash Memory Control Register Enable (FLSHE): Setting the FLSHE bit to 1 enables
read/write access to the flash memory control registers. If FLSHE is cleared to 0, the flash
memory control registers are deselected. In this case, the flash memory control register contents
are retained.
Bit 2—Reserved: Do not write 1 to this bit.
Bits 1 and 0—Internal Clock Select 1 and 0 (ICKS1, ICKS0): These bits control 8-bit timer
operation. See section 12, 8-Bit Timers, for details.
22.6
When pins are set to on-board programming mode, program/erase/verify operations can be
performed on the on-chip flash memory. There are two on-board programming modes: boot mode
and user program mode. The pin settings for transition to each of these modes are shown in table
22.6. For a diagram of the transitions to the various flash memory modes, see figure 22.3.
Only advanced mode setting is possible for boot mode.
In the case of user program mode, established in advanced mode or normal mode, depending on
the setting of the MD0 pin. In normal mode, only programming of a 56-kbyte area of flash
memory is possible.
Table 22.6 Setting On-Board Programming Modes
Note:
Bit 3
FLSHE
0
1
Mode Name
Boot mode
User program mode
* Can be used as I/O ports after boot mode is initiated.
On-Board Programming Modes
Description
Flash memory control registers deselected
Flash memory control registers selected
Section 22 ROM
Mode
CPU Operating Mode
Advanced mode
Advanced mode
Normal mode
(H8S/2138 F-ZTAT A-Mask Version, H8S/2134 F-ZTAT A-Mask Version)
Rev. 4.00 Jun 06, 2006 page 639 of 1004
MD1
0
1
0
1
MD0
0
P92
1 *
—
—
REJ09B0301-0400
P91
1 *
—
—
(Initial value)
P90
1 *
—
—