S1R72803F00A
74
EPSON
Address Register Name
Bit Symbol
R/W
Description
H.Rst S.Rst B.Rst
0x53
IsoDmaCtl
7: IsoChnlSel
R/W
0: IsoTxPktHdr0
1: IsoTxPktHdr1
6:
0:
1:
5:
0:
1:
4: SelTxPtr
R/W
0: Async Tx Pointer Select 1: ISO Tx Pointer Select 0x00
0x00
–
3: IsoFIFOEpty
R
0: IsoFIFO Empty
1: Non Empty
2: IsoFIFOClr
W
0: Normal
1: IsoFIFO Clear
1: IsoTxMon
R
0: Iso Tx Stop
1: Iso Tx Run
0: IsoStart
W
0: normal
1: Start
ISO TxDMA Control Register
Bit7 ISO Transmit Packet Header Channel Select
Selects the header area of an ISO Transmit packet from DMA. You can transmit a transmit packet from the
selected area. This bit selects “0”: ISOTxPktHdr0 or “1”: ISOTxPktHdr1. Since the ISOAsyncTxPktHdr0 and
ISOAsyncTxPktHdr1 areas overlap the AsyncTxPktHdr1 area, however, the firmware must decide how to use
this area.
Bit6..5 Reserved
Bit4 Select Transmit Pointer
Can switch the address pointed by the PostTxDataPtr of a transmit packet to one for Async or ISO. The
PostTxData Ptr indicates a pointer of current transmit address; “0” indicates it is for Async and “1” indicates
it is for ISO.
Bit3 ISO FIFO Empty
When the DMA-FIFO for ISO is empty, this bit becomes “0”. When it is not empty, it is “1”. This bit is read-
only and writing to this bit is ignored.
Bit2 ISO FIFO Clear
Clears the DMA-FIFO for ISO. Writing “1” to this bit clears the FIFO. After clearing it, this bit is automatically
restored to “0”.
Bit1 ISO Transmit Monitor
Indicates the transmit status of ISO. “1” indicates that an ISO packet is in transmission and “0” indicates that
no ISO packet is in transmission. This bit is read-only and writing to this bit is ignored.
Bit0 ISO Transmit Start
Transmits an ISO packet. Writing “1” to this bit starts to transmit an ISO packet. On completion of the
transmission, it is automatically restored to “0”. If you read this bit, it always indicates “0” regardless of
presence/absence of transmit.
