(4) Set H'FF as the PROM programmer buffer data for addresses H'8000 to H'1FFFF. The
H8/3334YF PROM size is 32 kbytes. Addresses H'8000 to H'1FFFF always read H'FF, so if H'FF
is not specified as programmer data, a verify error will occur.
(5) Notes on applying, releasing, and shutting*1 off the programming voltage (VPP)
•
Apply the programming voltage (VPP) after the rise of VCC, and release VPP before shutting off
VCC.
To prevent unintended programming or erasing of flash memory, in these power-on and
power-off timings, the application, release, and shutting-off of VPP must take place when the
microcontroller is in a stable operating condition as defined below.
Stable operating condition
The VCC voltage must be stabilized within the rated voltage range (VCC = 2.7 V to 5.5 V)*2
If VPP is applied, released, or shut off while the microcontroller’s VCC voltage is not within
the rated voltage range (VCC = 2.7 to 5.5 V)*2, since microcontroller operation is unstable,
the flash memory may be programmed or erased by mistake. This can occur even if VCC
0 V. To prevent changes in the VCC power supply when VPP is applied, be sure that the
power supply is adequately decoupled by inserting bypass capacitors.
=
Clock oscillation must be stabilized (the oscillation settling time must have elapsed), and
oscillation must not be stopped
When turning on VCC power, hold the RES pin low during the oscillation settling time
(tOSC1 = 20 ms), and do not apply VPP until after this time.
The microcontroller must be in the reset state, or in a state in which a reset has ended
normally (reset has been released) and flash memory is not being accessed
Apply or release VPP either in the reset state, or when the CPU is not accessing flash
memory (when a program in on-chip RAM or external memory is executing). Flash
memory cannot be read normally at the instant when VPP is applied or released. Do not read
flash memory while VPP is being applied or released.
For a reset during operation, apply or release VPP only after the RES pin has been held low
for at least ten system clock cycles (10ø).
The P and E bits must be cleared in the flash memory control register (FLMCR)
When applying or releasing VPP, make sure that the P or E bit is not set by mistake.
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RENESAS [ RENESAS TECHNOLOGY CORP ]
