102
8024A–AVR–04/08
ATmega8HVA/16HVA
Bits 1, 0 – SPR1, SPR0: SPI Clock Rate Select 1 and 0
These two bits control the SCK rate of the device configured as a Master. SPR1 and SPR0 have
no effect on the Slave. The relationship between SCK and the Oscillator Clock frequency f
osc is
shown in the following table:
18.5.2
SPSR – SPI Status Register
Bit 7 – SPIF: SPI Interrupt Flag
When a serial transfer is complete, the SPIF Flag is set. An interrupt is generated if SPIE in
SPCR is set and global interrupts are enabled. If SS is an input and is driven low when the SPI is
in Master mode, this will also set the SPIF Flag. SPIF is cleared by hardware when executing the
corresponding interrupt handling vector. Alternatively, the SPIF bit is cleared by first reading the
SPI Status Register with SPIF set, then accessing the SPI Data Register (SPDR).
Bit 6 – WCOL: Write Collision Flag
The WCOL bit is set if the SPI Data Register (SPDR) is written during a data transfer. The
WCOL bit (and the SPIF bit) are cleared by first reading the SPI Status Register with WCOL set,
and then accessing the SPI Data Register.
Bit 5:1 – Res: Reserved Bits
These bits are reserved bits in the ATmega8HVA/16HVA and will always read as zero.
Bit 0 – SPI2X: Double SPI Speed Bit
When this bit is written logic one the SPI speed (SCK Frequency) will be doubled when the SPI
is in Master mode (see Table 18-5 on page 102). This means that the minimum SCK period will
be two CPU clock periods. When the SPI is configured as Slave, the SPI is only guaranteed to
work at f
osc/4 or lower.
The SPI interface on the ATmega8HVA/16HVA is also used for program memory and EEPROM
downloading or uploading. See Table 27.6 on page 151 for serial programming and verification.
Table 18-5.
Relationship Between SCK and the Oscillator Frequency
SPI2X
SPR1
SPR0
SCK Frequency
00
0
f
osc/4
00
1
f
osc/16
01
0
f
osc/64
01
1
f
osc/128
10
0
f
osc/2
10
1
f
osc/8
11
0
f
osc/32
11
1
f
osc/64
Bit
7654
3210
SPIF
WCOL
SPI2X
SPSR
Read/Write
RRR
R
R/W
Initial Value
0000
相关PDF资料
ATSAM3N4AA-AU MCU FLASH 48-QFP
ATSAM3SD8CA-CU IC MCU 2X256KB CORTEX-M3 100-QFN
ATSAM3U1EB-CU IC MCU 64KB CORTEX-M3 144-TFBGA
ATSAM3X8EA-CU IC MCU 2X256KB CORTEX-M3 144-BGA
ATTINY12V-1SUR IC AVR MCU 1K FLASH 4MHZ 8-SOIC
ATTINY13-20SQR IC MCU AVR 1KB FLASH 20MHZ 8SOIC
ATTINY13A-MMUR MCU AVR 1KB FLASH 20MHZ 10DFN
ATTINY13V-10SUR MCU AVR 1KB FLASH 10MHZ 8SOIC
相关代理商/技术参数
ATMEGA8HVA-4CKUR 功能描述:8位微控制器 -MCU AVR 8KB FLSH 512B EE 1KB SRAM - 4 MHZ RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA8HVA-4TU 功能描述:8位微控制器 -MCU AVR 8KB, 512B EE 4MHz 1KB SRAM 1.8-9V RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA8HVA-4TUR 功能描述:8位微控制器 -MCU AVR 8KB FLSH 512B EE 1KB SRAM - 4 MHZ RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA8HVD-4MX 功能描述:8位微控制器 -MCU AVR 8KB, 512B EE 4MHz 1KB SRAM 2.1-8V RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA8L-8AC 功能描述:8位微控制器 -MCU AVR 8K FLASH 512B EE 1K SRAM ADC 3V RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA8L8AI 制造商:Atmel Corporation 功能描述:
ATMEGA8L-8AI 功能描述:8位微控制器 -MCU AVR 8K FLASH 512B EE 1K SRAM ADC 3V RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA8L-8AJ 功能描述:IC MCU AVR 8K 5V 8MHZ 32-TQFP RoHS:是 类别:集成电路 (IC) >> 嵌入式 - 微控制器, 系列:AVR® ATmega 标准包装:9 系列:87C 核心处理器:8051 芯体尺寸:8-位 速度:40/20MHz 连通性:UART/USART 外围设备:POR,WDT 输入/输出数:32 程序存储器容量:32KB(32K x 8) 程序存储器类型:OTP EEPROM 大小:- RAM 容量:256 x 8 电压 - 电源 (Vcc/Vdd):4.5 V ~ 5.5 V 数据转换器:- 振荡器型:内部 工作温度:0°C ~ 70°C 封装/外壳:40-DIP(0.600",15.24mm) 包装:管件