ADuCM310 Hardware Reference Manual
UG-549
Rev. C | Page 141 of 192
Bits
Bit Name
Description
Reset
Access
5
TX
SPI Tx IRQ status bit. Not available in DMA mode.
0x0
RC
0: CLR. Cleared to 0 when the SPI0STA register is read.
1: SET. Set to 1 when a transmit interrupt occurs. This bit is set when TIM in
SPI0CON is set and the required number of bytes have been transmitted.
4
TXUR
SPI Tx FIFO underflow.
0x0
RC
0: cleared to 0 when the SPI0STA register is read.
1: set to 1 when a transmit is initiated without any valid data in the Tx FIFO. This
bit generates an interrupt, except when TFLUSH is set in SPI0CON.
[3:1]
TXFSTA
SPI Tx FIFO status.
0x0
R
000: Tx FIFO empty.
001: 1 valid byte in FIFO.
010: 2 valid bytes in FIFO.
011: 3 valid bytes in FIFO.
100: 4 valid bytes in FIFO.
0
IRQ
SPI interrupt status.
0x0
RC
0: cleared to 0 after reading SPI0STA.
1: set to 1 when an SPI based interrupt occurs.
Receive Register
Address: 0x4002C004, Reset: 0x0000, Name: SPI0RX
Table 199. Bit Descriptions for SPI0RX
Bits
Bit Name
Description
Reset
Access
[15:8]
DMA_DATA_BYTE_2
8-bit receive buffer. These 8 bits are used only in the DMA mode, where all
FIFO accesses happen as half-word access. They return 0s if DMA is disabled.
0x0
R
[7:0]
DATA_BYTE_1
8-bit receive buffer.
0x0
R
Transmit Register
Address: 0x4002C008, Reset: 0x0000, Name: SPI0TX
Table 200. Bit Descriptions for SPI0TX
Bits
Bit Name
Description
Reset
Access
[15:8]
DMA_DATA_BYTE_2
8-bit transmit buffer. These 8 bits are used only in the DMA mode, where all
FIFO accesses happen as half-word access. They return 0s if DMA is disabled.
0x0
W
[7:0]
DATA_BYTE_1
8-bit transmit buffer.
0x0
W
Baud Rate Selection Register
Address: 0x4002C00C, Reset: 0x0000, Name: SPI0DIV
Table 201. Bit Descriptions for SPI0DIV
Bits
Bit Name
Description
Reset
Access
[15:9]
RESERVED
Reserved.
0x0
R
8
CSIRQ_EN
Enable interrupt on every CS edge in CONT mode. If this bit is set and the SPI
module is in continuous mode, any edge on CS generates an interrupt and the
corresponding status bits (CSRSG, CSFLG) are asserted. If this bit is clear, no
interrupt is generated. This bit has no effect if the SPI is not in continuous mode
and high speed mode.
0x0
RW
7
BCRST
Reset Mode for CSERR. If this bit is set, the bit counter is reset after a CS error
condition and the Cortex is expected to clear the SPI enable bit. If this bit is
clear, the bit counter continues from where it stopped. SPI can receive the
remaining bits when CS is asserted, and Cortex has to ignore the CSERR
interrupt. However, it is strongly recommended to set this bit for a graceful
recovery after a CS error.
0x0
RW