HD64F3048F16 Datasheet, PDF (647/903 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 18 ROM (H8/3048F-ONE: Single Power Supply, H8/3048B Mask ROM Version)
18.11 Notes on Flash Memory Programming/Erasing
The following describes notes when using the on-board programming mode, RAM emulation
function, and PROM mode.
1. Program/erase with the specified voltage and timing.
Applied voltages in excess of the rating can permanently damage the device.
Note that the pins FWE, V_PP, and MD2 have different absolute maximum ratings between the
H8/3048F-ONE (single power supply) and H8/3048F (dual power supply) models.
Use a PROM writer that supports the Renesas Technology 128 kbytes flash memory on-board
microcomputer device type.
Do not select the HN28F101 as the PROM writer. Otherwise, 12 V will be applied to the FWE
pin and this will permanently damage H8/3048F-ONE.
2. Notes on powering on/powering off (see figures 18.18 to 18.20)
Input a high level to the FWE pin after verifying Vcc. Before turning off Vcc, set the FWE pin
to a low level.
When powering on and powering off the Vcc power supply, fix the FWE pin low and set the
flash memory to the hardware protection mode.
Be sure that the powering on and powering off timing is satisfied even when the power is
turned off and back on in the event of a power interruption, etc. If this timing is not satisfied,
microcomputer runaway, etc., may cause overprogramming or overerasing and the memory
cells may not operate normally.
3. Notes on FWE pin High/Low switching (see figures 18.18 to 18.20)
Input FWE in the state microcomputer operation is verified. If the microcomputer does not
satisfy the operation confirmation state, fix the FWE pin low to set the protection mode.
To prevent erroneous programming/erasing of flash memory, note the following in FWE pin
High/Low switching:
a. Apply an input to the FWE pin after the Vcc voltage has stabilized within the rated voltage.
If an input is applied to the FWE pin when the microcomputer Vcc voltage does not satisfy
the rated voltage, flash memory may be erroneously programmed or erased because the
microcomputer is in the unconfirmed state.
b. Apply an input to the FWE pin when the oscillation has stabilized (after the oscillation
stabilization time).
When turning on the Vcc power, apply an input to the FWE pin after holding the RES pin
at a low level during the oscillation stabilization time. Do not apply an input to the FWE
pin when oscillation is stopped or unstable.
Rev. 3.00 Sep 27, 2006 page 619 of 872
REJ09B0325-0300