IC687BEM742使用方法,GE燃机模块
由于七条线路用于解码车载功能（第4节），VMIVME-3112板地址由八行地址位A08定义通过A15。电路板地址通过安装短路插头来编程“零”或低地址位跳线位置，并通过省略“一”或高位。地址位A06的权重为64字节位置。像例如，表5.4.2-1中所示的跳线布置将产生NNNN85XX十六进制的板地址*输入/输出访问模式通过正确选择跳线AM2进行编程条形图（AM2上有一条线）和AM2。选择短期非特权访问安装跳线AM2 bar（AM2上有一条线）。选择短监督访问忽略两个跳投。跳线AM2的安装允许电路板响应以下任一情况：访问类型。
IC687BEM742使用方法5.4.3模拟输入模式5.4.3.1差动或单端操作VMIVME-3112板出厂时配置了模拟输入用于差动操作。模拟输入模式由48个插座内的32个电阻器SIP（标记为RP1到RP 48）。如果VMIVME-3112保持部件侧朝上，前面板朝左，然后，SIP套接字形成六列。最左边的两列应始终安装SIP。两个中间立柱应安装SIP，以配置差分输入。最右边的两列应具有SIP安装用于配置单端输入。SIP是对称的。不会的向后安装会很痛苦。在单端模式下，外场接地感应输入可以用于补偿设备信号之间的电位差返回。如果安装了J1跨接导线，输入接头P3的针脚C1将用作所有单端输入的接地感应。板上有一个40.2 K电阻器VMIVME-3112将倾向于将该接地传感器拉至VME总线数字接地。如果安装了J2跨接导线（而不是J1），则单端输入将工作相对于VME总线数字接地（可能非常嘈杂）。建议使用该电路板用于差分输入模式。为了正确操作，任何输入引脚上的电压不得超过相对于VMEbus接地（+）或（-）12 V。隔离输入源将具有不确定的共模相对于VMEbus接地的电压。在这种情况下，可能需要为信号源提供VME接地参考。在差分模式下，通常没有接地参考可在VMIVME-3112的P3或P4上使用。VME接地在VME上可用背板。获取地面基准的另一种方法是安装跨接导线J1和J2。安装J1和J2后，输入通道0将不可用作差分输入，但P3上的针脚C1将被连接至VMEbus接地。通道0仍可用作单端输入。通过P3引脚C1的电流连续不得超过750 mA。
Since seven lines are used for decoding on-board functions (Section 4),
the VMIVME-3112 Board address is defined by eight lines, address bits A08
through A15.
The board address is programmed by installing shorting plugs at all
"zero" or LOW address bit jumper positions, and by omitting the shorting plugs at
the "one" or HIGH positions. Address bit A06 has a weight of 64 byte-locations. As
an example, the jumper arrangement shown in Table 5.4.2-1 would produce a
board address of NNNN85XX HEX.*
The I/O access mode is programmed by proper selection of jumpers AM2
bar (AM2 with a line over it) and AM2. To select short nonprivileged access install
jumper AM2 bar (AM2 with a line over it). To select short supervisory access omit
both jumpers. The installation of jumper AM2 allows the board to respond to either
type of access.
5.4.3 Analog Input Modes
5.4.3.1 Differential or Single-Ended Operation
The VMIVME-3112 Board is shipped with the analog inputs configured
for differential operation. The analog input mode is controlled by the positions of
32-resistor SIPs within 48 sockets (labeled RP1 through RP 48). If the
VMIVME-3112 is held with the component side up and the front panel facing left,
then the SIP sockets form six columns. The two left-most columns should always
have SIPs installed. The two middle columns should have SIPs installed to
configure differential inputs. The two right-most columns should have SIPs
installed to configure single-ended inputs. The SIPs are symmetrical. It will not
hurt to install them backwards.
In the single-ended mode, the external field ground sense input can be
used to compensate for the potential differences between equipment signal
returns. If the J1 jumper is installed, pin C1 of the input connector P3 serves as a
ground sense for all single-ended inputs. There is a 40.2 K resistor on board the
VMIVME-3112 which will tend to pull this ground sense to VME bus digital ground.
If the J2 jumper is installed (instead of J1) then the single-ended inputs will operate
relative to VME bus digital ground (which may be quite noisy). It is recommended
that the board be used in the differential input mode. FOR PROPER OPERATION, THE VOLTAGE ON ANY INPUT PIN MAY NOT EXCEED
(+) OR (-) 12 V RELATIVE TO THE VMEbus GROUND.
AN ISOLATED INPUT SOURCE WILL HAVE AN INDETERMINATE COMMON MODE
VOLTAGE RELATIVE TO VMEbus GROUND. IN SUCH CASES IT MAY BE NECESSARY TO
PROVIDE SIGNAL SOURCES WITH THE VME GROUND REFERENCE.
IN DIFFERENTIAL MODE THERE IS NORMALLY NO GROUND REFERENCE
AVAILABLE ON P3 OR P4 OF THE VMIVME-3112. VME GROUND IS AVAILABLE ON THE VME
BACKPLANE. AN ALTERNATE METHOD OF OBTAINING A GROUND REFERENCE IS TO
INSTALL JUMPERS J1 AND J2. WITH J1 AND J2 INSTALLED, INPUT CHANNEL 0 WOULD
NOT BE USABLE AS A DIFFERENTIAL INPUT BUT, PIN C1 ON P3 WOULD BE CONNECTED
TO VMEbus GROUND. CHANNEL 0 MAY STILL BE USED AS A SINGLE-ENDED INPUT.
CURRENT THROUGH PIN C1 ON P3 SHOULD NOT EXCEED 750 mA CONTINUOUS.
