Program check device for programmable controller

TL;DR: In this paper, an operating signal of a program check start indication key A included in a key section 16 is introduced to an address counter 17 and a program readout circuit reads out the contents stored in the specified address of program memory 11 in accordance with the contents of an address designated by the counter.

Abstract: PURPOSE:To enable to make program check again from the next address, by making a specified key operation, after an error in the program contents of a program memory is detected and displayed CONSTITUTION:An operating signal of a program check start indication key A included in a key section 16 is introduced to an address counter 17 A program readout circuit 18 reads out the contents stored in the specified address of a program memory 11 in accordance with the contents of an address designated by the counter 17 Error check such as parity error can be made for this storage contents with an error detection circuit 19 When an error is detected like this, the result is inputted to an error display driving circuit 20 and the address information and types of erors of the program memory 11 caused by the error are displayed 21 Although the operation of the error check is locked in this state, the program check is again made from the next address when a check continuity indicating key B of the key section 16 is operated