CM1K Hardware User’s Manual
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When REG is equal to 04, the DS pulse triggers a Write CAT. The RDY signal is pulled down for 19 cycles.
7.2.2
Recognize a vector
The sequence of instructions consists of 7 Write COMP, 1 Write LCOMP, 1 Read DIST and 1 Read CAT.
When REG is equal to 01, each DS pulse triggers a Write COMP. The RDY signal is pulled down for one cycle.
When REG is equal to 02, the DS pulse triggers a Write LCOMP. The RDY signal is pulled down for 3 cycles. The
UNC_l is pulled down at the last negative edge of G_CLK before RDY is pulled back up. This indicates that the input
vector is recognized by more than one neuron and that different categories are identified.
When REG is equal to 03 and RW_l remains high, the DS pulse triggers a Read DIST. The RDY signal is pulled down
for 18 cycles which is the duration of the Search and Sort looking for the firing neuron with the smallest distance
value. This distance is equal to 08.
When REG is equal to 04 and RW_l remains high, the DS pulse triggers a Read CAT. The RDY signal is pulled down
for 19 cycles which is the duration of the Search and Sort looking for the firing neuron with a distance register
equal to 08 and the smallest category value. This category is equal to 01.
Remark: Since it is known that the recognition status is uncertain (UNC_L is low), executing another series of Read
DIST followed by Read CAT would report the distance and category of the next neuron with the smallest distance.
7.2.3
Recognizing a vector received through the digital video bus
In the following example, RECO_EN and V_EN are both pulled up so the reco_logic of the chip can continuously
recognize the video data received through the V_CLK, V_FV, V_LV and V_DATA.
Immediately after the fall of V_FV, the B_BSY line rises indicating that the recognition stage is active and
communicating with the neurons.
The DS, RW_l, REG and DATA seen in the above diagram are generated internally by the reco_logic stage and
broadcasted to the parallel bus so the neurons of all the CM1K chips in the chain can participate to the recognition
(and not only the neurons of the CM1K with the active recognition stage).