Chapter 7 Reset - Fujitsu F2MC-8FX Hardware Manual

Table 7.2-1 Functions of Bits in Reset Source Register (RSRR)
Bit Name
bit7 Unused bits
HWDR:
bit6 Hardware watchdog
reset flag bit
CSVR:
bit5 Clock supervisory reset
flag bit
EXTS:
bit4
External reset flag bit
WDTR:
bit3
Watchdog reset flag bit
PONR:
bit2
Power-on reset flag bit
HWR:
bit1
Hardware reset flag bit
SWR:
bit0
Software reset flag bit
Note:
Reading the reset source register clears it. For this reason, if you wish to use the reset source
register for operation, we recommend moving the contents of the register to RAM.
The value read is always 0.
These bits are read-only. Any value written is meaningless.
This bit is set to "1" to indicate that a hardware watchdog reset has occurred.
Otherwise, the bit retains the value existing before the reset occurred.
• Read access to this bit sets it to "0".
• The bit is read-only. Any value written is meaningless.
When this bit is "1", indicates that a clock supervisory reset has been generated.
Otherwise, retains the value before the reset occurred.
• Read access to this bit sets it to "0".
• This bit is read-only. The written value carries no significance, and does not affect the operation.
• This bit is always "0" in products without clock supervisory. The written value carries no
significance and does not affect the operation.
This bit is set to "1" to indicate that an external reset has occurred.
Otherwise, the bit retains the value existing before the reset occurred.
• Read access to this bit sets it to "0".
• The bit is read-only. Any value written is meaningless.
This bit is set to "1" to indicate that a watchdog reset has occurred.
Otherwise, the bit retains the value existing before the reset occurred.
• Read access to this bit sets it to "0".
• The bit is read-only. Any value written is meaningless.
This bit is set to "1" to indicate that a power-on reset or low-voltage detection reset (option) has
occurred.
Otherwise, the bit retains the value existing before the reset occurred.
• The low-voltage detection reset function is provided for specific models.
• Read access to this bit sets it to "0".
• The bit is read-only. Any value written is meaningless.
This bit is set to "1" to indicate that a reset other than software resets has occurred. When any of bits
2 to 6 is set to "1", therefore, this bit is set to "1" as well.
Otherwise, the bit retains the value existing before the reset occurred.
• Read access to this bit sets it to "0".
• The bit is read-only. Any value written is meaningless.
This bit is set to "1" to indicate that a software reset has occurred.
Otherwise, the bit retains the value existing before the reset occurred.
• Read access to this bit or a power-on reset sets it to "0".
• The bit is read-only. Any value written is meaningless.
Function

CHAPTER 7 RESET

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