Ameba-D User Manual
User Manual All information provided in this document is subject to legal disclaimers. © REALTEK 2019. All rights reserved.
418
31
30
29
28
27
26
25
…
12
11
10
9
8
7
6
5
4
3
2
1
0
RSVD
DMARDL
R/W
Bit
Name
Access
Reset
Description
31:6
RSVD
N/A
-
Reserved
5:0
DMARDL
R/W
0x0
Receive Data Level. This bit field controls the level at which a DMA request is made by the
receive logic. The watermark level = 1; that is, dma_rx_req is generated when the
number of valid data entries in the receive FIFO is equal to or above this field value + 1, and
RDMAE=1. Refer to Table 19-6
for the field decode.
Table 19-6 DMARDL decode value
DMARDL value
Description
0000_0000
dma_rx_req is asserted when 1 or more data entry is present in transmit FIFO
0000_0001
dma_rx_req is asserted when 2 or more data entries are present in transmit FIFO
0000_0010
dma_rx_req is asserted when 3 or more data entries are present in transmit FIFO
0000_0011
dma_rx_req is asserted when 4 or more data entries are present in transmit FIFO
…
…
1111_1100
dma_rx_req is asserted when 253 or more data entries are present in transmit FIFO
1111_1101
dma_rx_req is asserted when 254 or more data entries are present in transmit FIFO
1111_1110
dma_rx_req is asserted when 255 or more data entries are present in transmit FIFO
1111_1111
dma_rx_req is asserted when 256 data entries are present in transmit FIFO
19.3.2.22
TXUICR
Name:
Transmit FIFO Underflow Interrupt Clear Register
Size:
1 bit
Address offset
:
0x58
Read/write access:
read
This register is present only if SPI is configured as serial-slave.
31
30
29
28
27
26
25
…
7
6
5
4
3
2
1
0
RSVD
TXUICR
R
Bit
Name
Access Reset
Description
31:1
RSVD
N/A
-
Reserved
0
TXUICR
R
0
When SPI is configured as serial-slave, this register is used to Clear Transmit FIFO Underflow
Interrupt. This register reflects the status of the interrupt. A read from this register clears the
ssi_txu_intr interrupt; writing has no effect.
19.3.2.23
SSRICR
Name:
SS_N Rising Edge Detect Interrupt Clear Register
Size:
1 bit
Address offset
:
0x5C
Read/write access:
read
This register is present only if SPI is configured as serial-slave.
31
30
29
28
27
26
25
…
7
6
5
4
3
2
1
0
RSVD
SSRICR
R
Bit
Name
Access
Reset
Description
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2019-05-15 10:08:03