LSI Logic Confidential
15-76
Serial I/O Port
Copyright © 2001, 2002 by LSI Logic Corporation. All rights reserved.
SPI DMA Receive Control Register (SPI_RX_CONTROL_REG_ADDR)
Offset = 0xBE0060
Read/Write
Default = 0x0000 0000
GO
Load Current Address Buffer Registers
3
This bit is used to control when ADDR_PTR1 and
ADDR_PTR2 for a particular DMA channel are loaded
into the “current buffer” address registers (ADDR_PTR3
and ADDR_PTR4) in double-buffer mode operation.
Note:
The maximum size for each SDRAM buffer transfer is 511
bytes. Therefore, the difference between ADDR_PTR2 and
ADDR_PTR1 should not exceed 511.
Note:
DoMiNo always runs in double-buffer mode. Single-buffer
(ring buffer) mode is not supported.
Go is set by software after the address range for the “next
buffer” is programmed (ADDR_PTR1/ADDR_PTR2).
Go is cleared by the hardware after these “next values”
are loaded. It is also cleared on reset.
MODE
Transfer Mode Select
2
This bit must always be set to ‘1’ so that the channel
operates in double-buffer mode.
FLUS
FIFO Flush
1
This is a self-clearing bit for flushing the DMA channel’s
two internal FIFOs.
For transmit channels, when FLUS is set, all data cur-
rently in the channel FIFOs is dropped.
For receive channels, all data currently in the channel
FIFOs is sent to the SDRAM address indicated by
ADDR_PTR3.
Setting FLUS does not terminate a transfer; it merely
dumps data (if transmit) or sends whatever data remains
in the FIFOs up to the SDRAM (if receive).
31
16
RSVD
15
4
3
2
1
0
RSVD
GO
MODE
FLUS
CHEN