DS90UB947-Q1: source code or script when the link is unstable

"""

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"""
############################
# DS90UB947-Q1 Init Code Example v1.1
# 947->948, Dual FPD-Link STP, 1920x1080@60Hz
############################

import time
import sys

# System dependant variables - adjust according to system 
UB947 = 0x18        # 947 I2C Address
UB948 = 0x58        # Remote 948 Address
StartAmbTemp = 25   # Example temperature measured by local sensor on PCB (Ambient temp around 947). In real system this should be read back from temp sensor during initialization 
Hres = 1920         # Expected horizontal active resolution
Vres = 1080         # Expected vertical active resolution 

def pollstate():
    count=0
    board.WriteI2C(UB947,0x23,0x80)
    board.WriteI2C(UB947,0x24,0x80)
    mask = int('11111',2)
    state = board.ReadI2C(UB947,0x24,1)
    while (state & mask) != 27:   #27 = 5'b11011
        time.sleep(0.01)  #10ms delay
        state = board.ReadI2C(UB947,0x24,1)
        count = count +1
        if count == 10:
            print "Error: Serializer is not in Normal state"
            return(1)
    
    board.WriteI2C(UB947,0x23,0x0)
    board.WriteI2C(UB947,0x24,0x0)

        

def initsequence():

    board.WriteI2C(UB947,0x03,0xDA) # Set I2C passthrough
    
    linked = 0
    retry = 0
    mask = int('10000000',2)
    # while linked == 0:
    #     STS = board.ReadI2C(UB947,0x5A,1)
    #     if ((STS & mask) != 0):
    #         linked = 1
    #         print "Deserializer Detected"
    #     else:
    #         time.sleep(0.1)
    #         retry = retry + 1
    #         if retry == 10:
    #             print "Error: No Deserializer Detected"
    #             return()

    board.WriteI2C(UB948,0x4A,0x01) # Disable OLDI outputs on 948 to prevent screen glitches from appearing during the init process 

    ##### Init A Sequence

    # Errata #5 and 6
    board.WriteI2C(UB947,0x5B,0x03) # Force dual FPD-Link, disable reset on PLL frequency change 

    # Errata #10
    board.WriteI2C(UB947,0x16,0x02) # Adjust BCC watchdog timer to minimum

    # Errata #11
    board.WriteI2C(UB947,0x04,0x90) # Prevent AVMUTE for non-HDCP systems



    state_error = pollstate()  # Poll 947 state machine prior to applying init B errata

    if state_error == 1:
        return()

    ##### Init B Sequence 

    # # Errata #2 (only for older non-eFuse devices)
    # board.WriteI2C(UB947,0x40,0x10)
    # board.WriteI2C(UB947,0x41,0x4A)
    # board.WriteI2C(UB947,0x42,0x3F)
    # board.WriteI2C(UB947,0x41,0x4B)

    # if StartAmbTemp < 10:
    #     board.WriteI2C(UB947,0x42,0x88)
    # else:
    #     board.WriteI2C(UB947,0x42,0x89)
    # board.WriteI2C(UB947,0x41,0x49)
    # board.WriteI2C(UB947,0x42,0x10)
    # board.WriteI2C(UB947,0x42,0x00)
    # board.WriteI2C(UB947,0x40,0x14)
    # board.WriteI2C(UB947,0x41,0x4A)
    # board.WriteI2C(UB947,0x42,0x3F)
    # board.WriteI2C(UB947,0x41,0x4B)
    # if StartAmbTemp < 10:
    #     board.WriteI2C(UB947,0x42,0x88)
    # else:
    #     board.WriteI2C(UB947,0x42,0x89)
    # board.WriteI2C(UB947,0x41,0x49)
    # board.WriteI2C(UB947,0x42,0x10)
    # board.WriteI2C(UB947,0x42,0x00)

    # Errata #3 
    board.WriteI2C(UB947,0x40,0x10)
    board.WriteI2C(UB947,0x41,0x49)
    board.WriteI2C(UB947,0x42,0x16)
    board.WriteI2C(UB947,0x41,0x47)
    board.WriteI2C(UB947,0x42,0x20)
    board.WriteI2C(UB947,0x42,0xA0)
    board.WriteI2C(UB947,0x42,0x20)
    board.WriteI2C(UB947,0x42,0x00)
    board.WriteI2C(UB947,0x41,0x49)
    board.WriteI2C(UB947,0x42,0x00)

    time.sleep(0.01)

    ##### Timing Confirmation 

    retry = 0
    Hconfirm = 0
    Vconfirm = 0
    while (retry < 3):
        board.WriteI2C(UB948,0x68,0x08) # Enable PATGEN BIST
        time.sleep(0.1) # Critical time delay - do not adjust to a shorter value 
        board.WriteI2C(UB948,0x68,0x19) # H active High monitor
        Hhigh = board.ReadI2C(UB948, 0x69, 1)
        board.WriteI2C(UB948,0x68,0x09) # H active Low monitor
        Hlow = board.ReadI2C(UB948, 0x69, 1)
        board.WriteI2C(UB948,0x68,0x39) # V active High monitor
        Vhigh = board.ReadI2C(UB948, 0x69, 1)
        board.WriteI2C(UB948,0x68,0x29) # V active Low monitor
        Vlow = board.ReadI2C(UB948, 0x69, 1)
        board.WriteI2C(UB948,0x68,0x00) # Disable PATGEN BIST

        mask = int('00111111',2)

        hlowmask = Hlow & mask
        hhighmask = Hhigh & mask
        vlowmask = Vlow & mask
        vhighmask = Vhigh & mask


        hhighmask = hhighmask << 6
        vhighmask = vhighmask << 6

        Hactive = hhighmask | hlowmask
        Vactive = vhighmask | vlowmask

        if Hactive != Hres:
            retry  = retry + 1
            board.WriteI2C(UB947,0x40,0x10) # Reset OLDI PLL
            board.WriteI2C(UB947,0x41,0x49)
            board.WriteI2C(UB947,0x42,0x16)
            board.WriteI2C(UB947,0x41,0x47)
            board.WriteI2C(UB947,0x42,0x20)
            board.WriteI2C(UB947,0x42,0xA0)
            board.WriteI2C(UB947,0x42,0x20)
            board.WriteI2C(UB947,0x42,0x00)
            board.WriteI2C(UB947,0x41,0x49)
            board.WriteI2C(UB947,0x42,0x00)
            time.sleep(0.1)
        else:
            Hconfirm = 1
        if Vactive != Vres:
            retry  = retry + 1
            board.WriteI2C(UB947,0x40,0x10) # Reset OLDI PLL
            board.WriteI2C(UB947,0x41,0x49)
            board.WriteI2C(UB947,0x42,0x16)
            board.WriteI2C(UB947,0x41,0x47)
            board.WriteI2C(UB947,0x42,0x20)
            board.WriteI2C(UB947,0x42,0xA0)
            board.WriteI2C(UB947,0x42,0x20)
            board.WriteI2C(UB947,0x42,0x00)
            board.WriteI2C(UB947,0x41,0x49)
            board.WriteI2C(UB947,0x42,0x00)
            time.sleep(0.1)
        else:
            Vconfirm = 1
        if (Hconfirm == 1) and (Vconfirm == 1):
            break

    if (retry > 2):
        print "Error: Timing confirmation failed. Double check expected video resolution and OLDI video input"  
        return()
    else:
        print "Initialization Complete"
        board.WriteI2C(UB948,0x01,0x01) # Digital reset to restart AEQ 
        time.sleep(0.1) # Allow time for 948 to relock 
        board.WriteI2C(UB948,0x4A,0x00) # Enable OLDI outputs on 948

initsequence()