1. A parallel processing device that computes a hierarchical neural network, comprising: a plurality of units, each of the plurality of units outputting an output value, the each of the plurality of units being identified by a characteristic unit number; the plurality of units being chained through a daisy chain control bus having a daisy chain order; a control section that outputs control data to the plurality of units, the control data including an input value and a selection unit number; and a storage section that stores a plurality of coupling weights, each of the plurality of coupling weights associating with layer information, the each of the plurality of units including: a data input section that receives the control data from the control section; a unit number match judgment section that judges whether the selection unit number matches the characteristic unit number; a unit processing section that computes the output value; and a data output section that outputs the output value to the control section when the unit number judgment section judges that the selection unit number matches the characteristic unit number; a token input section in communication with a token output section of a preceding unit of the plurality of units in the daisy chain order of the daisy chain control bus; a token output section in communication with a token input section of a next succeeding unit of the plurality of units in the daisy chain order of the daisy chain control bus; and a data output flag storage section in communication with the token output section and the data output section and having a data output flag indicating one of data having been outputted or data having been unoutputted; wherein in response to input of a token in the token input section, the data output section sets the data output flag of the data output flag storage section to data having been outputted; and wherein in response to the input value in the data input section, the token output section reads the data output flag from the data output flag storage section and outputs a token when the data output flag in the data output flag storage section is set to data having been outputted and, while outputting the token, the token output section resets the data output flag of the data output flag storage section to data having been unoutputted.