tmp88cu74 TOSHIBA Semiconductor CORPORATION, tmp88cu74 Datasheet - Page 37

• Manufacturer Part Number: tmp88cu74
• Description: Cmos 8-bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

1.6
Program counter
Stack pointer
General-purpose registers
Register bank selector
Jump status flag
Zero flag
Carry flag
Half carry flag
Sign flag
Overflow flag
Interrupt master enable flag
Interrupt individinal enable flags (EF)
Interrupt latchs
1.6.1
On-chip Hardware
Reset Circuit
address trap reset output, a watchdog timer reset output and a system clock reset output. Table
1.6.1 shows on-chip hardware initialization by reset action.
system clock reset is not initialized when power is turned on. The
“L” at the maximum 24/fc [s] (1.92 µs at 12.5 MHz) when power is turned on.
The TMP88CU74 has four types of reset generation procedures: an external reset input, an
The malfunction reset output circuit such as watchdog timer reset, address trap reset and
RESET
External Reset Input
power supply voltage within the operating voltage range and oscillation stable, a reset is
applied and the internal state is initialized.
execution starts at the vector address stored at addresses FFFFC to FFFFEH.
(W, A, B, C, D, E, H, L)
The
When the
When the
Sink open drain
RESET
VDD
Table 1.6.1 Initializing Internal Status by Reset Action
RESET
RESET
(RBS)
(IMF)
(PC)
(SP)
(HF)
pin contains a Schmitt trigger (hysteresis) with an internal pull-up resistor.
(CF)
(SF)
(VF)
(ZF)
(JF)
(IL)
pin is held at “L” level for at least 3 machine cycles (12/fc [s]) with the
pin input goes high, the reset operation is released and the program
(FFFFEH to FFFFCH)
Reset input
Initial Value
Malfunction reset
output circuit
Not initialized
Not initialized
Not initialized
Not initialized
Not initialized
Not initialized
Not initialized
Figure 1.6.1 Reset Circuit
0
1
0
0
0
88CU74-37
Prescaler and Divider of timing
generator
Output latches of I/O ports
On-chip Hardwear
Control registers
Watchdog timer
Watchdog timer reset
System clock reset
Address trap reset
RESET
pin can output level
Refer to I/O port
Refer to each of
control register
Initial Value
circuitry
Enable
TMP88CU74
0
2007-10-19
2003-02-17