8−24
8.25 Isochronous Receive Interrupt Event Register
The isochronous receive interrupt event set/clear register reflects the interrupt state of the isochronous receive
contexts. An interrupt is generated on behalf of an isochronous receive context if an INPUT_* command completes
and its interrupt bits are set to 1. Upon determining that the isochRx (bit 7) interrupt in the interrupt event register at
OHCI offset 80h/84h (see Section 8.21) has occurred, software can check this register to determine which context(s)
caused the interrupt. The interrupt bits are set to 1 by an asserting edge of the corresponding interrupt signal or by
writing a 1 in the corresponding bit in the set register. The only mechanism to clear a bit in this register is to write a
1 to the corresponding bit in the clear register. See Table 8−18 for a complete description of the register contents.
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Name Isochronous receive interrupt event
Type RRRRRRRRRRRRRRRR
Default 0000000000000000
Bit 15 14 13 12 11 109876543210
Name Isochronous receive interrupt event
Type R R R R R R R R R R R R RSC RSC RSC RSC
Default 0 0 0 0 0 0 0 0 0 0 0 0 X X X X
Register: Isochronous receive interrupt event
Offset: A0h set register
A4h clear register [returns the contents of isochronous receive interrupt event register
bit-wise ANDed with the isochronous receive mask register when read]
Type: Read/Set/Clear, Read-only
Default: 0000 000Xh
Table 8−18. Isochronous Receive Interrupt Event Register Description
BIT FIELD NAME TYPE DESCRIPTION
31−4 RSVD R Reserved. Bits 31−4 return 0s when read.
3 isoRecv3 RSC Isochronous receive channel 3 caused the interrupt event register bit 7 (isochRx) interrupt.
2 isoRecv2 RSC Isochronous receive channel 2 caused the interrupt event register bit 7 (isochRx) interrupt.
1 isoRecv1 RSC Isochronous receive channel 1 caused the interrupt event register bit 7 (isochRx) interrupt.
0 isoRecv0 RSC Isochronous receive channel 0 caused the interrupt event register bit 7 (isochRx) interrupt.