參數(shù)資料
型號: 20-101-0358
廠商: Rabbit Semiconductor
文件頁數(shù): 33/94頁
文件大?。?/td> 0K
描述: COMPUTER SINGLE-BOARD BL1820
標準包裝: 1
系列: Jackrabbit
模塊/板類型: 單板計算機模塊
適用于相關產品: BL1820
產品目錄頁面: 618 (CN2011-ZH PDF)
其它名稱: 316-1081
User’s Manual
35
3.8.3 Spectrum Spreader
Jackrabbit boards that carry the CE mark have a Rabbit 2000 microprocessor that features a
spectrum spreader, which helps to mitigate EMI problems. By default, the spectrum
spreader is on automatically for Jackrabbit BL1810 and BL1820 boards that carry the CE
mark when used with Dynamic C 7.32 or later versions, but the spectrum spreader may also
be turned off or set to a stronger setting. The spectrum spreader settings may be changed
through a simple configuration macro as shown below.
The spectrum spreader is off by default for Jackrabbit BL1800 models, and needs to be
enabled for them to be CE-compliant. To allow the flash memory and RAM chips to
accommodate the occasional higher frequencies associated with the spectrum spreader
being turned on for the Jackrabbit BL1800 models only, you will need at least one wait
state for both the flash memory and the RAM. The strong spectrum-spreading setting is not
needed for any Jackrabbit board.
The number of wait states is specified in the following code from the LIB\BOARDTYPES
library. (There are 0 wait states by default.)
#ifndef NUM_RAM_WAITST
#define NUM_RAM_WAITST 0
#endif
#ifndef NUM_FLASH_WAITST
#define NUM_FLASH_WAITST 0
#endif
There is no spectrum spreader functionality for Jackrabbit boards that do not carry the CE
mark or when using any Jackrabbit with a version of Dynamic C prior to 7.30.
1. Select the “Defines” tab from the Dynamic C Options > Project Options menu.
2. Normal spreading is the default, and usually no entry is needed. If you need to specify
normal spreading, add the line
ENABLE_SPREADER=1
For strong spreading, add the line
ENABLE_SPREADER=2
To disable the spectrum spreader, add the line
ENABLE_SPREADER=0
NOTE: The strong spectrum-spreading setting is not recommended since it may limit
the maximum clock speed or the maximum baud rate. It is unlikely that the strong set-
ting will be used in a real application.
3. Click OK to save the macro. The spectrum spreader will now remain off whenever you
are in the project file where you defined the macro.
相關PDF資料
PDF描述
20-101-0446 MODULE RABBITCORE RCM2130
AT25256-10PI-2.7 IC EEPROM 256KBIT 3MHZ 8DIP
345-030-524-801 CARDEDGE 30POS DUAL .100 GREEN
345-030-524-204 CARDEDGE 30POS DUAL .100 GREEN
345-030-524-202 CARDEDGE 30POS DUAL .100 GREEN
相關代理商/技術參數(shù)
參數(shù)描述
20-101-0383 功能描述:模塊化系統(tǒng) - SOM RCM2020 RabbitCore RoHS:否 制造商:Digi International 外觀尺寸:ConnectCore 9P 處理器類型:ARM926EJ-S 頻率:150 MHz 存儲容量:8 MB, 16 MB 存儲類型:NOR Flash, SDRAM 接口類型:I2C, SPI, UART 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 尺寸:1.97 in x 1.97 in x 6.1 in
20-101-0389 功能描述:子卡和OEM板 SR9200 16IN/8OUT RoHS:否 制造商:BeagleBoard by CircuitCo 產品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit
20-101-0390 功能描述:子卡和OEM板 SR9210 8 in/ 16 out RoHS:否 制造商:BeagleBoard by CircuitCo 產品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit
20-101-0391 功能描述:子卡和OEM板 SR9220 DIG I/O 8IN 8OUT RoHS:否 制造商:BeagleBoard by CircuitCo 產品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit
20-101-0392 功能描述:子卡和OEM板 SR9300 A/D 0-10V RoHS:否 制造商:BeagleBoard by CircuitCo 產品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit