M30240ECFP MITSUBISHI [Mitsubishi Electric Semiconductor], M30240ECFP Datasheet - Page 124

• Manufacturer Part Number: M30240ECFP
• Description: M30240 Group Specification
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

Specifications in this manual are tentative and subject to change
Usage Precautions
3.0 Usage
3.1 Usage Precautions
3.1.1 A-D Converter
3.1.2 Built-in PROM version
3.1.3 Dedicated Input Pins
• Write to each bit (except bit 6) of A-D control register 0, to each bit of A-D control register 1, and to
• When changing A-D operation mode, select analog input pin again.
• Using one-shot mode or single sweep mode
• Using repeat mode, repeat sweep mode 0 or repeat sweep mode 1
• All built-in PROM versions
• One Time PROM version
If a dedicated input pin is connected to a power supply that is different than the supply that Vcc is con-
nected to, a resistor (approximately 1k ohm) should be added between that input pin and the power
supply it is connected to, otherwise, if the dedicated input pin voltage is higher than Vcc, latch up could
occur.
bit 0 of A-D control register 2 when A-D conversion is stopped (before a trigger occurs).
In particular, when the Vref connection bit is changed from “0” to “1”, start A-D conversion after an
elapse of 1 s or longer.
Read the corresponding A-D register after confirming the A-D conversion is finished. (It is known by A-D con-
version interrupt request bit.)
Use the undivided main clock as the internal CPU clock.
High voltage is required to program to the built-in PROM. Be careful not to apply excessive voltage. Be espe-
cially careful during power-on.
One Time PROM versions shipped in blank, of which built-in PROMs are programmed by users, are also pro-
vided. For these microcomputers, a programming test and screening are not performed in the assembly pro-
cess and the following processes. To improve their reliability after programming, we recommend to program
and test as flow shown in Figure 115 before use.
Wiring for the Vpp pin of the One-Time PROM version should be as follows (Vpp pin is also used as the CNVss
pin):
• Make the length of wiring between the Vpp pin and Vss pin or Vcc pin the shortest possible.
• When the wiring length has to be longer, connect an approximately 5K ohm resistor in series from the Vpp
pin to the Vss pin or Vcc pin with the shortest possible wiring. This is because the Vpp pin is the power
source input pin for the built-in PROM. When programming in the built-in PROM, the impedance of the Vpp
pin is low to allow the electric current for wiring flow into the PROM. Because of this, noise can enter easily.
If noise enters the Vpp pin, abnormal instruction codes or data are read from the built-in PROM which may
cause a program runaway.
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SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Mitsubishi microcomputers
M30240 Group