Epson RX-8801SA/JE bit, bit, bit, bit, bit, bit, bit, bit, Data, Data, Data, Write, Address, Function, Description, Description, Description, interrupt events, interrupt events

"o" indicates write-protected bits. A zero is always read from these bits.

RX − 8801 SA / JE

8.4.2. Related registers for time update interrupt functions.

Address	Function	bit 7	bit 6	bit 5	bit 4	bit 3	bit 2	bit 1	bit 0
D	Extension Register	TEST	WADA	USEL	TE	FSEL1	FSEL0	TSEL1	TSEL0
E	Flag Register	{	{	UF	TF	AF	{	VLF	VDET
F	Control Register	CSEL1	CSEL0	UIE	TIE	AIE	{	{	RESET

∗)

∗Before entering settings for operations, we recommend writing a "0" to the UIE bit to prevent hardware interrupts from occurring inadvertently while entering settings.

∗When the RESET bit value is "1" time update interrupt events do not occur.

∗Although the time update interrupt function cannot be fully stopped, if "0" is written to the UIE bit, the time update interrupt function can be prevented from changing the /INT pin status to low.

1) USEL (Update Interrupt Select) bit

This bit is used to select "second" update or "minute" update as the timing for generation of time update interrupt events.

USEL	Data	Description
	0	Selects "second update" (once per second) as the timing for generation of
		interrupt events
Write/Read
	1	Selects "minute update" (once per minute) as the timing for generation of
		interrupt events

2) UF (Update Flag) bit

Once it has been set to "0", this flag bit value changes from "0" to "1" when a time update interrupt event occurs. When this flag bit = "1" its value is retained until a "0" is written to it.

UF	Data	Description
	0	The UF bit is cleared to zero to prepare for the next status detection
Write		∗ Clearing this bit to zero does not enable the /INT low output status to be cleared (to Hi-Z).
	1	This bit is invalid after a "1" has been written to it.
	0	Time update interrupt events are not detected.
Read
	1	Time update interrupt events are detected.
		(The result is retained until this bit is cleared to zero.)

3) UIE (Update Interrupt Enable) bit

When a time update interrupt event occurs (UF bit value changes from "0" to "1"), this bit selects whether to generate an interrupt signal (/INT status changes from Hi-Z to low) or to not generate it (/INT status remains Hi-Z).

UIE	Data	Description
		1) Does not generate an interrupt signal when a time update interrupt event
		occurs (/INT remains Hi-Z)
	0	2) Cancels interrupt signal triggered by time update interrupt event (/INT
		changes from low to Hi-Z).
Write/Read		∗ Even when the UIE bit value is "0" another interrupt event may change the /INT status to low (or
		may hold /INT = "L").
		When a time update interrupt event occurs, an interrupt signal is generated
	1	(/INT status changes from Hi-Z to low).
		∗ When a time update interrupt event occurs, low-level output from the /INT pin occurs only when
		the UIE bit value is "1". Up to 7.8 ms after the interrupt occurs, the /INT status is automatically
		cleared (/INT status changes from low to Hi-Z).

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