Renesas M-Station, Руководство пользователя

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M-Station Baseboard
8.3 Voltage Settings
The M-Station is capable of providing various V
DD
and V
PP
voltages to accommodate the various NEC
Electronics flash-programmable MCUs. Use JP3 and JP4 to set the appropriate voltage. See sections
3.4 and 3.6 of this user’s manual for the voltages and settings for these jumpers.
When the FP4MST program reads in a .PRC file for a particular MCU, FP4MST can check the V
DD
and
V
PP
voltages required by this device (contained in the .PRC file) against the settings of the jumpers on
the M-Station, if those settings are recorded by OPTMST. The M-Station software cannot directly
check the voltage selected by the jumpers, but it can compare the required voltages against the
recorded settings.
After selecting the appropriate voltage levels for a device by setting JP3 and JP4 on the M-Station, set
the JP3 Setting and JP4 Setting boxes to reflect the jumper connection used. When you select a
particular jumper setting, the associated V
DD
or V
PP
voltage is shown in the V
DD
Voltage and V
PP
Voltage boxes to the right of the jumper selection boxes.
8.4 PRC User-Specified Parameter Settings
The PRC User-Specified Parameters box enables you to adjust the timing parameters specified in
the .PRC file.
8.4.1 Additional Power On Time
Normally the FP4MST software switches on the V
DD
power to the flash device being programmed, and
then waits a specified amount of time to turn on V
PP
power and release reset. The amount of time to
wait after applying V
DD
power is specified in the .PRC file, with a minimum time of 30 milliseconds (ms).
For systems where there are significant capacitors connected to the V
DD
power on the micro-board, or
where a circuit is employed to hold down the RESET line for a period of time after V
DD
is applied, it
may be necessary to have the FP4MST software wait an additional time after turning power on to V
DD
.
For example, on the EV0338 board, an RC circuit generates a power-on reset, which may result in
RESET being low past the 30 ms normally allowed for power-on time.
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