C8051F581-IMR Silicon Labs, C8051F581-IMR Datasheet - Page 278

• Manufacturer Part Number: C8051F581-IMR
• Description: 8-bit Microcontrollers - MCU 50MIPS 128kB 8kB SPI
• Manufacturer: Silicon Labs

Specifications of C8051F581-IMR

• Rohs: yes
• Core: 8051
• Processor Series: C8051
• Data Bus Width: 8 bit

C8051F58x/F59x
SFR Definition 26.2. SPI0CN: SPI0 Control
SFR Address = 0xF8; Bit-Addressable; SFR Page = 0x00
278
Name
Reset
3:2
Bit
Type
7
6
5
4
1
0
Bit
NSSMD[1:0]
RXOVRN
TXBMT
WCOL
SPIEN
MODF
Name
SPIF
SPIF
R/W
7
0
SPI0 Interrupt Flag.
This bit is set to logic 1 by hardware at the end of a data transfer. If interrupts are
enabled, setting this bit causes the CPU to vector to the SPI0 interrupt service rou-
tine. This bit is not automatically cleared by hardware. It must be cleared by soft-
ware.
Write Collision Flag.
This bit is set to logic 1 by hardware (and generates a SPI0 interrupt) to indicate a
write to the SPI0 data register was attempted while a data transfer was in progress.
It must be cleared by software.
Mode Fault Flag.
This bit is set to logic 1 by hardware (and generates a SPI0 interrupt) when a mas-
ter mode collision is detected (NSS is low, MSTEN = 1, and NSSMD[1:0] = 01).
This bit is not automatically cleared by hardware. It must be cleared by software.
Receive Overrun Flag (valid in slave mode only).
This bit is set to logic 1 by hardware (and generates a SPI0 interrupt) when the
receive buffer still holds unread data from a previous transfer and the last bit of the
current transfer is shifted into the SPI0 shift register. This bit is not automatically
cleared by hardware. It must be cleared by software.
Slave Select Mode.
Selects between the following NSS operation modes:
(See Section 26.2 and Section 26.3).
00: 3-Wire Slave or 3-Wire Master Mode. NSS signal is not routed to a port pin.
01: 4-Wire Slave or Multi-Master Mode (Default). NSS is an input to the device.
1x: 4-Wire Single-Master Mode. NSS signal is mapped as an output from the
device and will assume the value of NSSMD0.
Transmit Buffer Empty.
This bit will be set to logic 0 when new data has been written to the transmit buffer.
When data in the transmit buffer is transferred to the SPI shift register, this bit will
be set to logic 1, indicating that it is safe to write a new byte to the transmit buffer.
SPI0 Enable.
0: SPI disabled.
1: SPI enabled.
WCOL
R/W
6
0
MODF
R/W
5
0
RXOVRN
R/W
Rev. 1.2
4
0
Function
3
NSSMD[1:0]
0
R/W
2
1
TXBMT
R
1
1
SPIEN
R/W
0
0