CM1K Hardware User’s Manual
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UNC_ is pulled down when the neurons recognizing the last input vector have different categories. This update
occurs each time a Write LCOMP is executed whether it is initiated by an external controller or by the internal
recognition logic of the chip. The actual update occurs at the 3
rd
negative edge of the clock during the execution of
the Write LCOMP. The UNC_ line is released at the next Write COMP.
The UNC_ line is also continuously latched in bit [2] of the NSR and RSR registers of the chip. at the positive edge of
the clock.
During a Write CAT, this line is asserted by the neurons if the last input vector is recognized as a novelty and must
be stored into a new neuron.
6.3
U
Neural network input lines
6.3.1
S_CHIP
By default the S_CHIP pin is pulled down to configure the parallel bus (DS, RW_l, REG and DATA) as bidirectional
and allow the neurons of multiple CM1K chips to receive commands synchronously and interact with one another.
If an architecture uses a single CM1K chip connected to a control unit via its I2C bus, then its parallel bus can be
disabled, thus reducing considerably the power consumption. If the reco logic of the chip is activate, it is possible
to overwrite the settings of the DATA lines through the RSR register. In that case, the RT_CAT register is latched on
the DATA lines at each CAT_VAL pulse.
6.3.2
DCI
Until the DCI line of a CM1K chip is high, its neurons are idle. As soon as the DCI line rises, the neurons of the chip
become active, meaning ready to learn and recognize.
In a configuration with multiple chips, the Daisy-Chain-In (DCI) line of the first CM1K chip must be high. For the
subsequent chips, the connection between their DCO and DCI lines allows to physically arrange them in a chain.
The DCI line of a CM1K must be connected to the DCO of the previous CM1K chip in the chain. Its status is then
controlled by the neurons of the previous chip.
6.4
Neural network output lines
6.4.1
DCO
The Daisy-Chain-Out (DCO) line of a CM1K must be connected to the DCI of the next CM1K chip in the chain, if
applicable. It is low by default and will rise when the last neuron of the chip gets committed. If this line is
connected to the DCI of another CM1K chip, the later will awake its neurons to become Ready-To-Learn.
6.4.2
RDY
The Ready line, RDY, is pulled down by the neurons during the execution of a command and released upon its
termination. It is updated at the positive edge of the system clock G_CLK whether or not the command is
recognized by the neurons.