Abstract: A small, low cost, programmable controller is described capable of solving user programs represented in networks having up to seven rows and eleven columns. A column solver is utilized to provide efficient and fast solution of the user control network. The programmable controller also solves calculate functions having multiple outputs to facilitate use of the output information in the control program.A programming panel using a CRT display shows one or more selected control networks and, in conjunction with the central processing unit of the programmable controller, provides for the insertion of networks between two existing networks. Since the networks are solved by the controller mainframe in a sequential fashion, this network insertion allows the user to optimize his or her control program when solution order of the networks is important.