 |
数据搜索系统，热门电子元器件搜索 |
|
|
数据搜索系统，热门电子元器件搜索 |
|
AT89C5122D-RDRUM 数据表(PDF) 43 Page - ATMEL Corporation |
|
|
|||||||||||||||||||||||||||||
AT89C5122D-RDRUM 数据表(HTML) 43 Page - ATMEL Corporation |
|
|
43 / 208 page  43 AT83R5122, AT8xC5122/23 4202F–SCR–07/2008 The CPU and peripherals clocks frequencies are defined in the table below. X1 and X2 Modes Use of on-chip oscillator When the CPU and Peripherals clocks are fed by the on-chip oscillator, the CPU and Peripherals can be configured independently in X1 or X2 mode depending on the fre- quencies wanted by the user. There is however one exception : the periperals can be configured in X2 mode while the CPU remains in X1 mode. This exception is handled by the hardware and the user does not need to take care of. The X1 or X2 modes can be individually selected for the CPU and each peripheral by means of CKCON0 and CKCON1 registers. At reset, the CPU and Peripherals are set all by default to X1 mode. In this mode, changing any peripheral to X2 mode has no effect. When X2 bit is set in CKCON0 register, CPU and All peripherals are automati- cally switched to X2 mode. It is then possible for the user to individually switch any peripheral back to X1 mode. In X1 mode (X2 bit cleared in CKCON0 regsiter), the PR1 prescaler is active while it is bypassed in X2 mode (X2 bit set in CKCON0 register). The X1 mode is true only when the prescaler PR1 is set to 1/2 (default condition at reset). CKS X2 FCK_IDLE 00FCK_XTAL1/(2*(16-CKRL)) 01FCK_XTAL1 10FCK_PLL/(2*(16-CKRL)) 11Not allowed Table 1. X1 and X2 Mode Selection CPU Peripherals Status Frequenci X1 mode X1 mode Allowed (default configuration at reset) FCK_IDLE = FCK_PERIPH X1 mode X2 mode Not Allowed by the hardware X2 mode X1 mode Allowed Once the CPU is switched to X2 mode, the user is free to switch any of the peripherals to X1 mode FCK_IDLE = 2*FCK_PERIPH X2 mode X2 mode Allowed Default configuration when CPU is switched to X2 mode FCK_IDLE = FCK_PERIPH |
|
链接网址 |
| ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 数据表链接 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
Chinese ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
