4/29/2020
Godson 3A1000 Processor User Manual
99
7: 0
LSB
8
RW
Store the lower 8 bits of the divider latch
Chinese name: Frequency Division Latch 2
Register bit width: [7: 0]
Offset: 0x01
Reset value: 0x00
Bit field
Bit field name
Bit width
access
description
7: 0
MSB
8
RW
Stores the upper 8 bits of the divider latch
10.4 SPI controller
The SPI controller has the following features:
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Godson 3A1000 Processor User Manual Part 1
● Full duplex synchronous serial data transmission
● Supports up to 4 variable-length byte transmission
● Main mode support
● Mode failure generates an error flag and issues an interrupt request
● Double buffer receiver
● Serial clock with programmable polarity and phase
● Can control SPI in wait mode
The base address of the physical address of the SPI controller module register is 0x1FE001F0.
10.4.1
Control Register ( SPCR )
Chinese name: Control Register
Register bit width: [7: 0]
Offset: 0x00
Reset value: 0x10
Bit field
Bit field name
Bit width access
description
7
Spie
1
RW
Interrupt output enable signal is high and effective
6
spe
1
RW
System work enable signal is highly effective
5
Reserved
1
RW
Keep
4
mstr
1
RW
master mode selection bit, this bit keeps 1
3
cpol
1
RW
Clock polarity bit
2
cpha
1
RW
Clock phase bit 1 is the opposite phase, and 0 is the same
1: 0
spr
2
RW
sclk_o crossover setting, need to be used with sper spre
10.4.2
Status Register ( SPSR )
Chinese name: Status Register
Register bit width: [7: 0]
Offset: 0x01
Reset value: 0x05
Bit field
Bit field name
Bit width access
description
7
spif
1
RW
Interrupt flag bit 1 indicates that there is an interrupt request, write 1 to clear
6
wcol
1
RW
Write register overflow flag bit is 1 indicates that it has overflowed, write 1 to