HD64F2357F20V Datasheet, PDF (644/1049 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-chip Microcomputer H8S Family / H8S/2300 Series

VCC
RES
FWE
t_osc1
t_bmv
Memory read Auto-program mode
mode
Auto-erase mode
Command wait
state
t_dwn
Command
wait state
Normal/
abnormal end
identification
Don't care
Don't care
Note: Except in auto-program mode and auto-erase mode, drive the FWE input pin low.
Figure 19-32 Oscillation Stabilization Time, Programmer Mode Setup Time, and Power Supply Fall Sequence
19.13.10 Notes on Memory Programming
• When programming addresses which have previously been programmed, carry out auto-erasing before auto-
programming.
• When performing programming using PROM mode on a chip that has been programmed/erased in an on-board
programming mode, auto-erasing is recommended before carrying out auto-programming.
Notes: 1. The flash memory is initially in the erased state when the device is shipped by Renesas Technology. For other
chips for which the erasure history is unknown, it is recommended that auto-erasing be executed to check and
supplement the initialization (erase) level.
2. Auto-programming should be performed once only on the same address block.
19.14 Flash Memory Programming and Erasing Precautions
Precautions concerning the use of on-board programming mode, the RAM emulation function, and PROM mode are
summarized below.
Use the specified voltages and timing for programming and erasing: Applied voltages in excess of the rating can
permanently damage the device. Use a PROM programmer that supports Renesas Technology microcomputer device
types with 128-kbyte on-chip flash memory.
Do not select the HN28F101 setting for the PROM programmer, and only use the specified socket adapter. Incorrect use
will result in damaging the device.
Powering on and off (see figures 19-33 to 19-35): Do not apply a high level to the FWE pin until V_CC has stabilized.
Also, drive the FWE pin low before turning off V_CC.
When applying or disconnecting V_CC, fix the FWE pin low and place the flash memory in the hardware protection state.
The power-on and power-off timing requirements should also be satisfied in the event of a power failure and subsequent
recovery.
FWE application/disconnection (see figures 19-33 to 19-35): FWE application should be carried out when MCU
operation is in a stable condition. If MCU operation is not stable, fix the FWE pin low and set the protection state.
The following points must be observed concerning FWE application and disconnection to prevent unintentional
programming or erasing of flash memory:
• Apply FWE when the V_CC voltage has stabilized within its rated voltage range. Apply FWE when oscillation has
stabilized (after the elapse of the oscillation settling time).
• In boot mode, apply and disconnect FWE during a reset.
Rev.6.00 Oct.28.2004 page 614 of 1016
REJ09B0138-0600H