CI687K01 3BSE043660R1處理控制模塊,ABB說(shuō)明書(shū)
MC2chip和可選控制器中都提供了看門(mén)狗定時(shí)器VMEchip2。計(jì)時(shí)器獨(dú)立但并行運(yùn)行。當(dāng)如果啟用了看門(mén)狗定時(shí)器，則必須在編程時(shí)間，否則將超時(shí)?？撮T(mén)狗計(jì)時(shí)器可能是編程生成系統(tǒng)復(fù)位信號(hào)、本地復(fù)位信號(hào)或電路板如果超時(shí)，則發(fā)出故障信號(hào)。請(qǐng)參閱中的VMEchip2和MC2chipMVME172 VME嵌入式控制器程序員參考指南有關(guān)詳細(xì)的編程信息。
CI687K01 3BSE043660R1處理控制模塊看門(mén)狗定時(shí)器邏輯在VMEchip2和MC2chip中重復(fù)亞瑟士。因?yàn)閂MEchip2中的看門(mén)狗定時(shí)器功能是MC2chip（系統(tǒng)重置功能）中該功能的超集，定時(shí)器在VMEchip2中，除MVME172LX不包括VMEbus接口（“否VMEbus接口”選項(xiàng)）。軟件可編程硬件中斷8個(gè)軟件可編程硬件中斷由VMEchip2。這些中斷允許軟件創(chuàng)建硬件中斷。請(qǐng)參閱MVME172 VME嵌入式控制器中的VMEchip2詳細(xì)編程信息的程序員參考指南。本地總線超時(shí)MVME172LX在VMEchip2和本地總線的MC2chip。當(dāng)定時(shí)器啟用且本地總線訪問(wèn)超時(shí)，傳輸錯(cuò)誤確認(rèn)（TEA）信號(hào)發(fā)送到本地總線主機(jī)。超時(shí)值可由軟件選擇8μs，64微秒、256微秒或無(wú)限。本地總線計(jì)時(shí)器在VMEbus綁定循環(huán)。VMEbus綁定周期由VMEbus計(jì)時(shí)訪問(wèn)計(jì)時(shí)器和VMEbus全局計(jì)時(shí)器。請(qǐng)參閱VMEchip2和MVME172 VME嵌入式控制器程序員的MC2chip有關(guān)詳細(xì)編程信息的參考指南。MC2chip還為MVME172LX提供本地總線超時(shí)邏輯沒(méi)有可選的VMEbus接口（即沒(méi)有VMEchip2）。訪問(wèn)計(jì)時(shí)器邏輯在VMEchip2和MC2chip中重復(fù)亞瑟士。因?yàn)閂MEchip2中的本地總線計(jì)時(shí)器可以檢測(cè)到非車(chē)載訪問(wèn)和MC2chip本地總線計(jì)時(shí)器不能，計(jì)時(shí)器在除MVME172LX版本外，所有情況下均使用VMEchip2
不包括VMEbus接口（“無(wú)VMEbus接口選項(xiàng)”）。
A watchdog timer is provided in both the MC2chip and the optional
VMEchip2. The timers operate independently but in parallel. When the
watchdog timers are enabled, they must be reset by software within the
programmed time or they will time out. The watchdog timers may be
programmed to generate a SYSRESET signal, local reset signal, or board
fail signal if they time out. Refer to the VMEchip2 and the MC2chip in the
MVME172 VME Embedded Controller Programmer’s Reference Guide
for detailed programming information.
The watchdog timer logic is duplicated in the VMEchip2 and MC2chip
ASICs. Because the watchdog timer function in the VMEchip2 is a
superset of that function in the MC2chip (system reset function), the timer
in the VMEchip2 is used in all cases except for the version of the
MVME172LX which does not include the VMEbus interface ("No
VMEbus Interface" option).
Software-Programmable Hardware Interrupts
Eight software-programmable hardware interrupts are provided by the
VMEchip2. These interrupts allow software to create a hardware interrupt.
Refer to the VMEchip2 in the MVME172 VME Embedded Controller
Programmer’s Reference Guide for detailed programming information.
Local Bus Timeout
The MVME172LX provides timeout functions in the VMEchip2 and the
MC2chip for the local bus. When the timer is enabled and a local bus
access times out, a Transfer Error Acknowledge (TEA) signal is sent to the
local bus master. The timeout value is selectable by software for 8 μsec, 64
μsec, 256 μsec, or infinite. The local bus timer does not operate during
VMEbus bound cycles. VMEbus bound cycles are timed by the VMEbus
access timer and the VMEbus global timer. Refer to the VMEchip2 and the
MC2chip in the MVME172 VME Embedded Controller Programmer’s
Reference Guide for detailed programming information.
The MC2chip also provides local bus timeout logic for MVME172LXs
without the optional VMEbus interface (i.e., without the VMEchip2).The access timer logic is duplicated in the VMEchip2 and MC2chip
ASICs. Because the local bus timer in the VMEchip2 can detect an
offboard access and the MC2chip local bus timer cannot, the timer in the
VMEchip2 is used in all cases except for the version of the MVME172LX
which does not include the VMEbus interface ("No VMEbus Interface
option").
