21 I
2
S
21-20
Seiko Epson Corporation
S1C33L26 TECHNICAL MANUAL
D[15:11] Reserved
D10
WEIF: I
2
S FIFO Whole Empty Interrupt Flag Bit
Indicates whether the cause of I
2
S FIFO whole empty interrupt has occurred or not.
1 (R):
Cause of interrupt has occurred
0 (R):
No cause of interrupt has occurred (default)
1 (W):
Flag is reset
0 (W):
Ignored
When all data (four stereo data) has been read from the FIFO to transmit, the I
2
S module sets WEIF to
1, indicating that the FIFO is empty. If I
2
S FIFO whole empty interrupts are enabled (WEIE = 1), an in-
terrupt request is sent simultaneously to the ITC. The interrupt handler needs to fill the FIFO with four
stereo data (16 bits
×
2 channels (L & R)
×
4). Then reset WEIF by writing 1 at the end of the interrupt
handler.
D9
HEIF: I
2
S FIFO Half Empty Interrupt Flag Bit
Indicates whether the cause of I
2
S FIFO half empty interrupt has occurred or not.
1 (R):
Cause of interrupt has occurred
0 (R):
No cause of interrupt has occurred (default)
1 (W):
Flag is reset
0 (W):
Ignored
When a free space for two stereo data becomes available in the FIFO, the I
2
S module sets HEIF to 1. If
I
2
S FIFO half empty interrupts are enabled (HEIE = 1), an interrupt request is sent simultaneously to
the ITC. The interrupt handler needs to fill the FIFO with two stereo data (16 bits
×
2 channels (L & R)
×
2). Then reset HEIF by writing 1 at the end of the interrupt handler.
D8
OEIF: I
2
S FIFO One Empty Interrupt Flag Bit
Indicates whether the cause of I
2
S FIFO one empty interrupt has occurred or not.
1 (R):
Cause of interrupt has occurred
0 (R):
No cause of interrupt has occurred (default)
1 (W):
Flag is reset
0 (W):
Ignored
When a free space for one stereo data becomes available in the FIFO, the I
2
S module sets OEIF to 1. If
I
2
S FIFO one empty interrupts are enabled (OEIE = 1), an interrupt request is sent simultaneously to the
ITC. The interrupt handler needs to fill the FIFO with one stereo data (16 bits
×
2 channels (L & R)
×
1).
Then reset OEIF by writing 1 at the end of the interrupt handler.
D[7:3]
Reserved
D2
WEIE: I
2
S FIFO Whole Empty Interrupt Enable Bit
Enables or disables I
2
S FIFO whole empty interrupts.
1 (R/W): Interrupt enabled
0 (R/W): Interrupt disabled (default)
Setting WEIE to 1 enables I
2
S FIFO whole empty interrupt requests to the ITC. Setting it to 0 disables
interrupts.
D1
HEIE: I
2
S FIFO Half Empty Interrupt Enable Bit
Enables or disables I
2
S FIFO half empty interrupts.
1 (R/W): Interrupt enabled
0 (R/W): Interrupt disabled (default)
Setting HEIE to 1 enables I
2
S FIFO half empty interrupt requests to the ITC. Setting it to 0 disables in-
terrupts.
D0
OEIE: I
2
S FIFO One Empty Interrupt Enable Bit
Enables or disables I
2
S FIFO one empty interrupts.
1 (R/W): Interrupt enabled
0 (R/W): Interrupt disabled (default)