Rainbow Electronics DS2172 - Manual (Page 7)

DS2172
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PATTERN SET REGISTERS
(MSB) (LSB)
PS31 PS30 PS29 PS28 PS27 PS26 PS25 PS24
PS23 PS22 PS21 PS20 PS19 PS18 PS17 PS16
PS15 PS14 PS13 PS12 PS11 PS10 PS9 PS8
PS7 PS6 PS5 PS4 PS3 PS2 PS1 PS0
4.0 PATTERN LENGTH REGISTER
Length Bits LB4 to LB0 determine the length of the
pseudorandom polynomial or programmable repetitive
pattern that is generated and detected. With the
pseudorandom patterns, the “Tap A” feedback position
of the pattern generator is always equal to the value in
the Pattern Length Register (PLR). Please refer to Fig-
ure 2 for a block diagram of the pattern generator and to
Tables 4 and 5 for some programming examples.
PLR: PATTERN LENGTH REGISTER (Address=04 Hex)
(MSB) (LSB)
– – – LB4 LB3 LB2 LB1 LB0
SYMBOL POSITION NAME AND DESCRIPTION
– PLR1.7 Not Assigned. Should be set to 0 when written to.
– PLR1.6 Not Assigned. Should be set to 0 when written to.
– PLR1.5 Not Assigned. Should be set to 0 when written to.
LB4 PLR1.4 Length Bit 4.
LB3 PLR1.3 Length Bit 3.
LB2 PLR1.2 Length Bit 2.
LB1 PLR1.1 Length Bit 1.
LB0 PLR1.0 Length Bit 0.
5.0 POLYNOMIAL TAP REGISTER
Polynomial Tap Bits PT4 – PT0 determine the feedback
position of Tap B connected to the XOR input of the pat-
tern generator. Feedback Tap B provides one of two
feedback paths within the pattern generator. Please
refer to Figure 2 for a block diagram of the pattern gener-
ator and to Tables 4 and 5 for register programming
examples.
PTR: POLYNOMIAL TAP REGISTER (Address=05 Hex)
(MSB) (LSB)
– – – PT4 PT3 PT2 PT1 PT0
SYMBOL POSITION NAME AND DESCRIPTION
– PTR.7 Not Assigned. Should be set to 0 when written to.
– PTR.6 Not Assigned. Should be set to 0 when written to.
– PTR.5 Not Assigned. Should be set to 0 when written to.
PT4 PTR.4 Polynomial Tap Bit 4.
PSR3
(addr.=00 Hex)
PSR2
(addr.=01 Hex)
PSR1
(addr.=02 Hex)
PSR0
(addr.=03 Hex)