RELIANCE 45C380自動(dòng)化輸入模塊
DS1384看門狗定時(shí)器中的時(shí)間功能可由用戶自行使用。看門狗定時(shí)器提供一個(gè)看門狗報(bào)警窗口，間隔時(shí)間在0.01到99.99秒之間。非易失性RAM在本手冊(cè)的NVRAM部分進(jìn)行了說明。看門狗報(bào)警可在軟件控制下生成VME SYSFAIL。系統(tǒng)命令寄存器的第8位（見表3-1）用于啟用此選項(xiàng)。系統(tǒng)命令寄存器為2字節(jié)寬，位于內(nèi)存地址$D800E。注意：要使用此選項(xiàng)，必須將看門狗定時(shí)器中斷輸出設(shè)置為電平模式（請(qǐng)參閱看門狗命令寄存器位4）。此外，看門狗報(bào)警通過一個(gè)雙狀態(tài)標(biāo)頭（E8）連接到CPU復(fù)位或系統(tǒng)NMI，或兩者都不連接。如果跳線設(shè)置在2-4位置，用戶可以指示看門狗警報(bào)重置CPU；如果跳線處于4-6位置，則啟動(dòng)非屏蔽中斷（NMI）；或者如果跳線被完全移除，則兩者都沒有。
The Time of Day feature in the DS1384 Watchdog Timer is available for use by the user at their discretion. The Watchdog Timer provides a Watchdog Alarm window and interval timing between 0.01 and 99.99 seconds. The Non-Volatile RAM is explained in the NVRAM section of this manual. The Watchdog Alarm can, under software control, generate a VME SYSFAIL. Bit 8 of the System Command register (see Table 3-1) is used to enable this option. The System Command Register is 2 bytes wide located at memory address $D800E. NOTE: The Watchdog Timer Interrupt output must be set to Level Mode (see Watchdog Command Register Bit 4) to use this option. In addition, the Watchdog Alarm is connected via a two state header (E8) to either or neither the CPU reset or the system NMI. The user can direct the Watchdog Alarm to reset the CPU if the jumper is set in the 2-4 position; to initiate a Non-Maskable Interrupt (NMI) if the jumper is in the 4-6 position; or neither if the jumper is completely removed.
