P0924JH端子模塊,P0924JH使用配置教程
讀取和寫入數(shù)據(jù)表的Modbus命令需要一個(gè)參考（起點(diǎn)），并且有些情況下，分?jǐn)?shù)是多少。提供的Modbus命令參考和PLC數(shù)據(jù)表
PLC中RTU模塊訪問的元件不一定等于以下所述。
最初，Modbus協(xié)議僅用于訪問4個(gè)不同的數(shù)據(jù)表，并且寫入數(shù)據(jù)量有限數(shù)據(jù)RTU模塊通過執(zhí)行參考映射來擴(kuò)展這些限制。RTU模塊包含PLC數(shù)據(jù)表的地圖，并為每個(gè)數(shù)據(jù)分配一系列相關(guān)的Modbus參考桌子因此，用戶只需簡單地通過一個(gè)Modbus命令即可訪問多個(gè)PLC數(shù)據(jù)表
P0924JH端子模塊更改參考。上表描述了Modbus參考的細(xì)分區(qū)域訪問適當(dāng)?shù)臄?shù)據(jù)表。每個(gè)型號的PLC CPU包含每個(gè)數(shù)據(jù)表的不同最大點(diǎn)數(shù)。在期間在RTU模塊初始化時(shí)，詢問CPU的每個(gè)數(shù)據(jù)表的大小。應(yīng)該aModbus參考，并在該命令后立即撥打號碼其中n=數(shù)字0到9，符號#和*，可能包括下面列出的撥號修飾符。調(diào)制解調(diào)器將以撥號修改器確定的方式撥打指定的號碼。表盤
除；修飾符，必須出現(xiàn)在字符串的末尾。在本例中，調(diào)制解調(diào)器脈沖撥打9位數(shù)字，等待撥號音，然后撥號音撥打數(shù)字然后撥打123-4567。最后，調(diào)制解調(diào)器在結(jié)束后返回到命令模式已撥打數(shù)字。P修飾符使調(diào)制解調(diào)器以每秒10個(gè)脈沖的固定速率進(jìn)行脈沖或旋轉(zhuǎn)撥號。T修飾符使調(diào)制解調(diào)器使用DTMF（雙音多頻）信號撥號（與“，”修飾符使調(diào)制解調(diào)器暫停。例如，撥打長途服務(wù)時(shí)調(diào)制解調(diào)器必須首先撥打本地接入號碼，然后暫停足夠長的時(shí)間，以接收服務(wù)撥號音?！?，”在從PBX系統(tǒng)撥號時(shí)也很有用，因?yàn)閮纱握埱笾g可能會花費(fèi)相當(dāng)長的時(shí)間
并獲得第二撥號音或“外部”線路。
@modifier使調(diào)制解調(diào)器等待一個(gè)或多個(gè)響鈴3秒，然后等待5秒
在處理撥號字符串中的下一個(gè)符號之前靜音。這在訪問以下系統(tǒng)時(shí)非常有用：
不要提供撥號音。
The Modbus commands which read and write to data tables require a reference (starting point) and, in
some cases, the number of points. The Modbus command reference provided and the PLC data table
element accessed by the RTU module in the PLC are not necessarily equal as described below.
Originally, the Modbus protocol was only meant to access 4 different data tables with limited writing of
data. The RTU module expands these limitations by performing reference mapping. The RTU module
contains a map of PLC data tables and assigns a range of associated Modbus references to each data
table.Therefore, the user can access more than one PLC data table with a single Modbus command by simply
changing the reference. The tables above describe the sub-divided regions of the Modbus reference to
access the appropriate data table.Each model of the PLC CPU contains a different maximum number of points for each data table. During
initialization of the RTU module, the CPU is interrogated for the size of each of its data tables. Should a
Modbus reference andDial the Number Immediately Following this Command
Where n = digits 0 to 9, the symbols # and *, and may include the dial modifiers listed below.
The modem will dial the number specified in the manner determined by the dial modifiers. The dial
modifiers may appear anywhere within the dial string with the exception of the ; modifier which must
appear at the end of the string.In this example the modem pulse dials a 9-digit number, waits for a dial tone, then tone dials the digits
713. It then dials the number 123-4567. Finally, the modem returns to the command mode after the final
digit has been dialed.
The P modifier causes the modem to pulse or rotary dial at a fixed rate of 10 pulses per second.
The T modifier causes the modem to dial using DTMF (Dual-tone multifrequency) signals (the same as
those used by “touch-tone” telephones)The "," modifier causes the modem to pause. When dialing a long distance service, for example, the
modem must first dial the local access number, then pause long enough for the services dial tone. The ","
is also useful when dialing from a PBX system where considerable time may elapse between requesting
and getting a secondary dial tone or "outside" line.
The @ modifier causes the modem to wait for 3 seconds for one or more rings followed by 5 seconds of
silence before processing the next symbol in the dial string. This is useful when accessing systems that
do not provide a dial tone.
