6F3B0250
7. Instructions
Note
·This instruction is only effective for the T2 I/O modules connected to the
·The special module can be designated not only by the assigned register, but also by the mounting position. The mounting position is designated by a constant data for the operand A as follows.
H
Slot number (hexadecimal)
Unit number (hexadecimal)
In the
·The READ instruction is not executed as error in the following cases. In these cases, the instruction error flag (ERF = S051) is set to ON. If the ERF is set to ON once, it remains ON until resetting to OFF by user program.
(1)When the operand A is other than a valid constant (see above) or XW/YW register.
(2)When no answer error occurs with the designated special module.
(3)When the number of words transferred exceeds 256 words.
(4)When the source table of transfer is out of the valid range.
(5)When the destination table of transfer is out of the valid range.
·The READ instruction can be programmed in the main program and in the interrupt program.
If this instruction is programmed in both, the instruction in the main program should be executed in interrupt disable state. Refer to EI (FUN 140) and DI (FUN 141) instructions.
264 T1/T1S User’s Manual
CTi Automation - Phone: 800.894.0412 - Fax: 208.368.0415 - Web: www.ctiautomation.net - Email: info@ctiautomation.net