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- TITLE SUPER_FRAME_PAL
- PATTERN SUPER FRAME PAL FOR T1 INTERFACE
- REVISION P1.02
- AUTHOR STEVE PATTERSON AND THERESA SHAFER
- COMPANY
- DATE 1/16/87
- ; This PAL counts the T1 Frames and controls the Signal Bits extraction
- ; process, including Fly Wheeling. It also provides various other
- ; signals which indicate the frames with signal bits
- ; The counter is reset with either RSTB or when frame detection is SUNK
- ; and frame 1 occurs from two different sources (FRM1 & SOF).
-
- CHIP SUPER_FRAME PAL16R6
-
- ;PINS
- ;1 2 3 4 5 6 7 8 9 10
- T1_CKB RSTB FRM1B SUNK SOF NC NC NC NC GND
-
- ;11 12 13 14 15 16 17 18 19 20
- OEB NC Q3 Q2 Q1 Q0 FRM_6 FRM_12 NC VCC
-
- ;INPUTS:T1_CKB ACTIVE LOW EXTERNAL T1 CLOCK
- ; RSTB ACTIVE LOW MASTER RESET
- ; SOF LAST KNOWN START OF FRAME
- ; SUNK ACTIVE HIGH SIGNAL INDICATING "IN FRAME SYNC"
- ; OEB ACTIVE LOW OUTPUT ENABLE INPUT
-
- ;OUTPUTS:Q(3-0) STATE VARIABLES
- ; FRM_6 CLOCK SIGNAL WHICH INDICATES SIGNAL BIT A
- ; FRM_12 CLOCK SIGNAL WHICH INDICATES SIGNAL BIT B
-
-
- EQUATIONS
-
- /Q3 := /Q2 * Q1 * Q0
- + /Q3 * /Q2
- + /Q3 * /Q1
- + /Q3 * /Q0
- + /FRM1B * SOF * SUNK
- + /RSTB
-
- /Q2 := Q2 * Q1 * Q0
- + /Q2 * Q3
- + /Q2 * /Q1
- + /Q2 * /Q0
- + /FRM1B * SOF * SUNK
- + /RSTB
-
- /Q1 := Q1 * Q0
- + /Q1 * /Q0
- + /FRM1B * SOF * SUNK
- + /RSTB
-
- /Q0 := Q0
- + /FRM1B * SOF * SUNK
- + /RSTB
-
- /FRM_6 := Q3 + /Q2 + Q1 + Q0
-
- /FRM_12 := /Q3 + Q2 + /Q1 + Q0
-
- SIMULATION
-
- TRACE_ON T1_CKB RSTB FRM1B SOF SUNK
- Q3 Q2 Q1 Q0 FRM_6 FRM_12
-
-
- SETF /OEB ; ENABLE OUTPUT
- /RSTB ; RESET REGISTERS
- /T1_CKB ; INITIALIZE THE CLOCK PIN
- CLOCKF T1_CKB
- SETF RSTB /SOF FRM1B SUNK
- CLOCKF T1_CKB
-
- FOR I:=1 TO 24 DO
- BEGIN
- CLOCKF T1_CKB
- END
-
- SETF /SUNK SOF /FRM1B
- CLOCKF T1_CKB
- SETF /SUNK /SOF /FRM1B
- CLOCKF T1_CKB
- SETF /SUNK SOF FRM1B
- CLOCKF T1_CKB
- SETF /SUNK /SOF FRM1B
- CLOCKF T1_CKB
- SETF SUNK SOF /FRM1B
- CLOCKF T1_CKB
- SETF SUNK /SOF /FRM1B
- CLOCKF T1_CKB
- SETF SUNK /SOF FRM1B
- CLOCKF T1_CKB
- SETF SUNK SOF FRM1B
- CLOCKF T1_CKB
- TRACE_OFF