Pattern Generator Board Theory - HP 1660CP Series User Manual

The Analyzer Hardware

Pattern Generator board theory

Pattern Generator board theory
Pattern Generator Board
Loop Register
The loop register holds the programmable vector flow information. When the
module reaches the end of the vector listing, the loop register is queried for
the RAM address location of the next user-programmed vector. In many
cases, the next vector address location would be the start of the vector
listing. Consequently, the vectors would continue to loop from the end of the
listing back to the beginning until you instruct the module to stop.
RAM
Consisting of five 256Kx16 VRAM ICs and RAM addressing circuitry, the RAM
stores the desired patterns that appear at the module output. The RAM
addressing circuitry is merely a counter which addresses the pattern
locations in RAM. When the end of the vector listing is reached, the
addressing circuitry is loaded from the loop register with the address of the
first vector of the listing to provide an uninterrupted vector loop. The RAM
output is sent to the Output Driver circuit where the patterns are presented
in a logic configuration usable by the output pods.
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