Fujitsu MB91319 Series Hardware Manual page 215

[bit4] OVFLE
This bit is the overflow interrupt request enable bit.
0 Interrupt request is disabled.
1 Interrupt request is enabled.
[bit3, bit2] Unused bits
These bits are unused.
[bit1] Reserved
This bit is a reserved bit. Be sure to write 0 at writing.
[bit0] ST
This bit is the PWC start bit.
0 PWC stops.
1 PWC operates.
CHAPTER 8 16-BIT PULSE WIDTH COUNTER
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