
ML62Q1000 Series User's Manual
Chapter 3 Reset Function
FEUL62Q1000
3-10
3.3.2 System Reset Mode
The LSI is transferred to the system reset mode when a reset occurs by any cause, except for resets caused by the block
control register (BRECON 0 to 3) and the software reset control register (SOFTRCON) as well as a CPU reset by the
BRK instruction.
The transition to the system reset mode has the highest priority over any other processing. Thus any process in progress
up until then will be aborted.
In the system reset mode, the following processes are performed.
1.
The fundamental hardware for the LSI operation, such as the power supply circuit and oscillation circuit, is
initialized. In addition, functions chosen by the code option are configured. The INITE bit of the reset status register
(RSTAT) is set to "1" if an abnormality occurs during the initialization and configuration.
See the Chapter 26 "Code Option" for details of the code option.
2.
Peripheral circuits, and special function registers (SFRs) with their initial values defined are initialized. See
Appendix A "Registers" and chapters for respective functions for the initial values of the SFRs.
3.
The CPU is initialized.
-
All the registers in the CPU are initialized.
-
The contents of addresses 0x0000, 0x0001 in segment 0 of the program memory are set to the stack pointer
(SP).
-
The contents of addresses 0x0002, 0x0003 in segment 0 of the program memory are set to the program counter
(PC).
4.
The transition to the program run mode takes place when the reset is released.
See "nX-U16/100 Core Instruction Manual" for details of registers (SP, PC, PSW) in the CPU, ELEVEL and the BRK
instruction.
[Note]
Ÿ
In system reset mode, the contents of data memory (RAM) and SFRs that have an undefined initial value
are not initialized. Initialize them by the software.
3.3.3 Reset Input Pin Reset
Asserting the "L" level to the reset input pin causes the reset state, as well as causing the RSTR bit of the reset status
register (RSTAT) to be set to "1". Then, negating the reset input pin to the "H" level causes the reset to be released and
the program begins to run.
To cause a reset to occur, assert the "L" level which is longer than the reset activation pulse width (P
RST
).
Figure 3-2 shows reset input pin reset operation waveforms.
Figure 3-2 Reset Input Pin Reset Operation Waveforms
The reset input pin is also used to debug software using the on-chip debug emulator or to write a program to the flash
memory using the ISP function. In these cases, the POR bit is set to "1"and RSTR bit is reset to "0".
See Chapter 28 "On-chip Debug Function" and Chapter 25 "Flash Memory" for how to use the reset input pin.
[Note]
Ÿ
The reset input pin has neither pull-up nor pull-down resistors built-in. Have a pull-up register externally.
Reset input pin
(RESET_N)
Internal reset signal
P
RST
Содержание ML62Q1000 Series
Страница 17: ...Chapter 1 Overview...
Страница 112: ...Chapter 2 CPU and Memory Space...
Страница 154: ...Chapter 3 Reset Function...
Страница 166: ...Chapter 4 Power Management...
Страница 196: ...Chapter 5 Interrupts...
Страница 248: ...Chapter 6 Clock generation Circuit...
Страница 274: ...Chapter 7 Low Speed Time Base Counter...
Страница 291: ...Chapter 8 16 Bit Timer...
Страница 320: ...Chapter 9 Functional Timer FTM...
Страница 382: ...Chapter 10 Watchdog Timer...
Страница 402: ...Chapter 11 Serial Communication Unit...
Страница 456: ...Chapter 12 I2 C Bus Unit...
Страница 491: ...Chapter 13 I2 C Master...
Страница 512: ...Chapter 14 DMA Controller...
Страница 531: ...Chapter 15 Buzzer...
Страница 550: ...Chapter 16 Simplified RTC...
Страница 559: ...Chapter 17 GPIO...
Страница 594: ...Chapter 18 External Interrupt Function...
Страница 612: ...Chapter 19 CRC Generator...
Страница 632: ...Chapter 20 Analog Comparator...
Страница 644: ...Chapter 21 D A Converter...
Страница 655: ...Chapter 22 Voltage Level Supervisor...
Страница 676: ...Chapter 23 Successive Approximation Type A D Converter...
Страница 709: ...Chapter 24 Regulator...
Страница 714: ...Chapter 25 Flash Memory...
Страница 743: ...Chapter 26 Code Option...
Страница 750: ...Chapter 27 LCD Driver...
Страница 788: ...Chapter 28 On Chip Debug Function...
Страница 795: ...Chapter 29 Safety Function...
Страница 813: ...Appendix A...
Страница 881: ...Revision History...