MPC555
/
MPC556
DUAL-PORT TPU RAM (DPTRAM)
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
18-9
After the entire RAM has been read and a signature has been calculated, the MISC
sets the MISF bit in the DPTMCR. The host should poll this bit and enter a handling
routine when the bit is found to be set.
The signature should be then read from the MISRH and MISRL registers and the host
determines if it matches the predetermined signature.
The MISRH and MISRL registers are updated each time the MISC completes reading
the entire RAM regardless of whether or not the previous signature has been read or
not. This ensures that the host reads the most recently generated signature.
The MISC can be disabled by clearing the MISEN bit in the DPTMCR. Note that the
reset state of the MPC555 / MPC556 MISEN is disabled.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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