BENTLY 146031-01 3500/22M框架接口模块
多路开关。使用MVME712M模块时，黄色当LAN通电时，MVME712M前面板上的LED（DS1）亮起可用，表明多路开关良好。MVME177通过二极管提供SCSI终端电源以及位于P2适配器板上的1安培多功能开关F1。如果多开关熔断（即打开），SCSI设备可能无法运行或者可能功能不稳定。使用P2适配器板时通过MVME712M和SCSI总线连接到MVME712M，MVME712M前面板上的绿色LED（DS2）有SCSI终端电源时亮起。
BENTLY 146031-01 3500/22M框架接口模块如果LED闪烁在SCSI总线操作期间，应检查多路开关。中止开关S1当通过软件启用时，嵌入式前面板中止开关在用户可编程级别生成中断。通常情况下用于中止程序执行并返回177Bug调试器固件位于MVME177 EPROM中。VMEchip2中的中止开关中断器是一个连接到中止开关的边缘敏感断续器。这对断续器进行过滤，以消除开关反弹。复位开关S2嵌入式前面板重置开关重置所有车载设备，如果板是系统控制器，则驱动SYSRESET*。重置开关可能被软件禁用。VMEchip2包括全局和本地重置驱动程序。什么时候该芯片作为VMEbus系统控制器、复位驱动器运行通过断言VMEbus信号提供全局系统重置系统重置*。系统重置*可由以下方式生成：❏ 复位开关❏ 通电复位❏ 看门狗超时❏ LCSR中的控制位SYSRESET*保持断言状态至少200毫秒，如VMEbus规范。类似地，VMEchip2提供输入信号和控制位本地重置操作。通过设置控制位，软件可以将电路板保持在重置状态，从而禁用故障电路板系统正常运行。本地重置驱动程序为即使VMEchip2不是系统控制器也启用。A.
本地重置可通过以下方式生成：❏ 复位开关❏ 通电复位❏ 看门狗超时❏ VMEbus系统重置*❏ GCSR中的控制位
the polyswitch. When using the MVME712M module, the yellow
LED (DS1) on the MVME712M front panel lights when LAN power
is available, indicating that the polyswitch is good.
The MVME177 provides SCSI terminator power through a diode
and a 1 amp polyswitch F1 located on the P2 Adapter Board. If the
polyswitch is blown (i.e., open), the SCSI devices may not operate
or may function erratically. When the P2 Adapter Board is used
with an MVME712M and the SCSI bus is connected to the
MVME712M, the green LED (DS2) on the MVME712M front panel
lights when there is SCSI terminator power. If the LED flickers
during SCSI bus operation, the polyswitch should be checked.ABORT Switch S1
When enabled by software, the recessed front panel ABORT switch
generates an interrupt at a user-programmable level. It is normally
used to abort program execution and return to the 177Bug
debugger firmware located in the MVME177 EPROMs.
The ABORT switch interrupter in the VMEchip2 is an
edge-sensitive interrupter connected to the ABORT switch. This
interrupter is filtered to remove switch bounce. RESET Switch S2
The recessed front panel RESET switch resets all onboard devices,
and drives SYSRESET* if the board is system controller. The RESET
switch may be disabled by software.
The VMEchip2 includes both a global and a local reset driver. When
the chip operates as the VMEbus system controller, the reset driver
provides a global system reset by asserting the VMEbus signal
SYSRESET*. A SYSRESET* may be generated by the following:
❏ RESET switch
❏ Power up reset
❏ Watchdog timeout
❏ Control bit in the LCSR
SYSRESET* remains asserted for at least 200 msec, as required by
the VMEbus specification.
Similarly, the VMEchip2 provides an input signal and a control bit
to initiate a local reset operation. By setting a control bit, software
can maintain a board in a reset state, disabling a faulty board from
participating in normal system operation. The local reset driver is
enabled even when the VMEchip2 is not the system controller. A
local reset may be generated by:
❏ RESET switch
❏ Power up reset
❏ Watchdog timeout
❏ VMEbus SYSRESET*
❏ Control bit in the GCSR
