參數(shù)資料
型號: TMS320DM643GDK500
廠商: Texas Instruments, Inc.
元件分類: 數(shù)字信號處理
英文描述: Video/Imaging Fixed-Point Digital Signal Processo
中文描述: 視頻/影像定點數(shù)字信號Processo
文件頁數(shù): 44/123頁
文件大?。?/td> 1205K
代理商: TMS320DM643GDK500
www.ti.com
3.6.2
Watchdog Block
/512
OSCCLK
WDCR (WDPS(2:0))
WDCLK
WDCNTR(7:0)
WDKEY(7:0)
Bad Key
Good Key
1
0
1
WDCR (WDCHK(2:0))
Bad
WDCHK
Key
WDCR (WDDIS)
Clear Counter
SCSR (WDENINT)
Watchdog
Prescaler
Generate
Output Pulse
(512 OSCCLKs)
8-Bit
Watchdog
Counter
CLR
WDRST
WDINT
Watchdog
55 + AA
Key Detector
XRS
Core-reset
WDRST
(A)
Internal
Pullup
TMS320F2808, TMS320F2806
TMS320F2801, UCD9501
Digital Signal Processors
SPRS230F–OCTOBER 2003–REVISED SEPTEMBER 2005
Normally, when the input clocks are present, the watchdog counter decrements to initiate a watchdog
reset or WDINT interrupt. However, when the external input clock fails, the watchdog counter stops
decrementing (i.e., the watchdog counter does not change with the limp-mode clock). In addition to this,
the device will be reset and the “Missing Clock Status” (MCLKSTS) bit will be set. These conditions could
be used by the application firmware to detect the input clock failure and initiate necessary shut-down
procedure for the system.
NOTE
Applications in which the correct CPU operating frequency is absolutely critical should
implement a mechanism by which the DSP will be held in reset, should the input clocks
ever fail. For example, an R-C circuit may be used to trigger the XRS pin of the DSP,
should the capacitor ever get fully charged. An I/O pin may be used to discharge the
capacitor on a periodic basis to prevent it from getting fully charged. Such a circuit would
also help in detecting failure of the flash memory and the V
DD3VFL
rail.
The watchdog block on the 280x is similar to the one used on the 240x and 281x devices. The watchdog
module generates an output pulse, 512 oscillator clocks wide (OSCCLK), whenever the 8-bit watchdog up
counter has reached its maximum value. To prevent this, the user disables the counter or the software
must periodically write a 0x55 + 0xAA sequence into the watchdog key register which will reset the
watchdog counter.
Figure 3-12
shows the various functional blocks within the watchdog module.
A.
The WDRST signal is driven low for 512 OSCCLK cycles.
Figure 3-12. Watchdog Module
The WDINT signal enables the watchdog to be used as a wakeup from IDLE/STANDBY mode.
44
Functional Overview
相關(guān)PDF資料
PDF描述
TMS320C6211PYP167 FIXED-POINT DIGITAL SIGNAL PROCESSORS
TMS320C6211PQ150 FIXED-POINT DIGITAL SIGNAL PROCESSORS
TMS320C6211PQ120 FIXED-POINT DIGITAL SIGNAL PROCESSORS
TMS320C6211PQ100 FIXED-POINT DIGITAL SIGNAL PROCESSORS
TMS320VC5421PGE DIGITAL SIGNAL PROCESSOR
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TMS320DM643GDK600 制造商:Rochester Electronics LLC 功能描述:VIDEO/IMAGING FIXED-POINT DIGITAL SIGNAL PROCESSOR - Bulk
TMS320DM643GNZ500 制造商:Texas Instruments 功能描述:DSP FIX PT 32BIT 500MHZ 4000MIPS 548FCBGA - Trays
TMS320DM643GNZ600 制造商:Rochester Electronics LLC 功能描述:VIDEO/IMAGING FIXED-POINT DIGITAL SIGNAL PROCESSOR - Bulk 制造商:Texas Instruments 功能描述:
TMS320DM6441AZWT 功能描述:數(shù)字信號處理器和控制器 - DSP, DSC DaVinci Dig Media SOC RoHS:否 制造商:Microchip Technology 核心:dsPIC 數(shù)據(jù)總線寬度:16 bit 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:2 KB 最大時鐘頻率:40 MHz 可編程輸入/輸出端數(shù)量:35 定時器數(shù)量:3 設(shè)備每秒兆指令數(shù):50 MIPs 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 封裝 / 箱體:TQFP-44 安裝風(fēng)格:SMD/SMT
TMS320DM6441BZWT 功能描述:數(shù)字信號處理器和控制器 - DSP, DSC DaVinci Dig Media Sys-on-Chip RoHS:否 制造商:Microchip Technology 核心:dsPIC 數(shù)據(jù)總線寬度:16 bit 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:2 KB 最大時鐘頻率:40 MHz 可編程輸入/輸出端數(shù)量:35 定時器數(shù)量:3 設(shè)備每秒兆指令數(shù):50 MIPs 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 封裝 / 箱體:TQFP-44 安裝風(fēng)格:SMD/SMT