KUKA E93DA113I4B531伺服模塊,KSD1-32使用教程
COMMREQ梯形圖指令有四個(gè)輸入和一個(gè)輸出：COMMREQ梯形圖指令啟用輸入：必須為邏輯1才能啟用COMMREQ指令。建議：?jiǎn)⒂眠壿嬍沁^(guò)渡（“一次”）線(xiàn)圈的觸點(diǎn)。IN：命令塊第一個(gè)字的內(nèi)存位置。它可以是任何有效的字型內(nèi)存中的地址（%R、%AI或%AQ）。例如，%R00100 at IN將指示命令塊的起始地址為%R00100。SYSID：一個(gè)十六進(jìn)制值，給出所需模塊的機(jī)架和插槽位置COMMREQ正在定位。
KUKA E93DA113I4B531伺服模塊高位字節(jié)（十六進(jìn)制數(shù)的前兩位）包含機(jī)架號(hào)，低字節(jié)包含插槽號(hào)。下表顯示了一些SYSID示例：當(dāng)激活COMMREQ梯形圖指令時(shí)，啟動(dòng)通信請(qǐng)求在PLC掃描期間。此時(shí)，來(lái)自PLC的命令通過(guò)通信請(qǐng)求發(fā)送至PROFIBUS主模塊（PBM）。在每個(gè)請(qǐng)求結(jié)束時(shí)，PLC CPU將請(qǐng)求的狀態(tài)報(bào)告給狀態(tài)字，是PLC內(nèi)存中由狀態(tài)字指定的位置命令塊中的指針。在上圖中，PBM顯示在CPU機(jī)架中，通信發(fā)生在PLC背板。如果PBM位于擴(kuò)展機(jī)架或遠(yuǎn)程機(jī)架中，則命令數(shù)據(jù)通過(guò)擴(kuò)展電纜或遠(yuǎn)程電纜通過(guò)CPU機(jī)架的背板發(fā)送連接到包含PBM的機(jī)架，并穿過(guò)該機(jī)架的背板連接到PBM。 COMMREQ指令應(yīng)通過(guò)過(guò)渡線(xiàn)圈的觸點(diǎn)啟用。
如果在梯形圖程序中使用多個(gè)COMMREQ，請(qǐng)驗(yàn)證之前的COMMREQ在執(zhí)行另一個(gè)命令之前已成功執(zhí)行。這是可以做到的通過(guò)檢查狀態(tài)字和FT（故障）輸出。
如果啟用輸入未激活，則FT輸出保持為假。這意味著如果COMMREQ由一個(gè)過(guò)渡（單次）觸點(diǎn)啟用，當(dāng)故障發(fā)生時(shí)，F(xiàn)T僅一次PLC掃描的輸出高。為了捕捉故障發(fā)生的事實(shí)，您需要可以將故障輸出編程為設(shè)定線(xiàn)圈，在掃描結(jié)束。然后需要額外的邏輯來(lái)重置故障輸出線(xiàn)圈
確認(rèn)故障后，在下一次執(zhí)行COMMREQ之前。
The COMMREQ ladder
instruction has four inputs and one
output:
Figure 4-1. COMMREQ Ladder Instruction
Enable Input: Must be Logic 1 to enable the COMMREQ Instruction. It is recommended that
the enabling logic be a contact from a transition (“one-shot”) coil.
IN: The memory location of the first word of the Command Block. It can be any valid
address in word-type memory (%R, %AI, or %AQ). For example, %R00100 at IN would
indicate that the starting address of the Command Block is %R00100.
SYSID: A hexadecimal value that gives the rack and slot location of the module that the
COMMREQ is targeting. The high byte (first two digits of the hex number) contains the
rack number, and the low byte contains the slot number. The table below shows some
examples of SYSIDs:A Communications Request is initiated when a COMMREQ ladder instruction is activated
during the PLC scan. At this time, a command from the PLC via the Communications
Request is sent to the PROFIBUS Master module (PBM).
At the conclusion of every request, the PLC CPU reports the status of the request to the
Status Word, which is a location in PLC memory that is designated by the Status Word
Pointer in the Command Block.
In the figure above, the PBM is shown in the CPU rack and communications occur over
the PLC backplane. If the PBM is located in an expansion or remote rack, the commands
and data are sent over the CPU rack’s backplane, through the expansion or remote cable
to the rack containing the PBM, and across that rack’s backplane to the PBM. COMMREQ instructions should be enabled by a contact from a transition coil.
