AN2866 Freescale Semiconductor / Motorola, AN2866 Datasheet - Page 21

• Manufacturer Part Number: AN2866
• Description: Migrating from the MC68332 to the ColdFire MCF523x
• Manufacturer: Freescale Semiconductor / Motorola

2.4.2.7.2
The Message Digest Hardware Accelerator (MDHA) computes a single message digest (or hash or
integrity check) value of all the data presented on the input bus, using either the MD5 or SHA-1 algorithms
for bulk data hashing. The MDHA includes these distinctive features:
2.4.2.7.3
The random number generator (RNG) module is capable of generating 32-bit random numbers. It is
designed to comply with FIPS-140 standards for randomness and non-determinism.
2.4.2.8
There are four independent, DMA-transfer-generating 32-bit timers (DTIM0, DTIM1, DTIM2, DTIM3)
on the MCF523x. Each timer module incorporates a 32-bit timer with a separate register set for
configuration and control. The timers can be configured to operate from the system clock or from an
external clock source using one of the DTINx signals. If the system clock is selected, it can be divided by
16 or 1. The input clock is further divided by a user-programmable 8-bit prescaler that clocks the actual
timer counter register (TCRn). The timer counter may be set as free running or restarting, and a timer
resolution of 13.33-ns at 75 MHz can be achieved.
Each of these timers can be configured for input capture or reference compare mode. By setting the internal
registers, each timer may be configured to assert an external signal, generate an interrupt (maskable) on a
particular event or cause a DMA transfer. Input capture may be set to sense either edge transition on the
input pin. Output compare supports programmable modes for the output pin toggling.
2.5
During reset, the MC68332 latches the values on the MODCK pin to determine boot options such as clock
mode, CSBOOT port size, and chip select configuration. The MCF523x determines operating modes at
reset in a similar manner, but the MCF523x has more boot chip configuration options. The MCF523x gives
the user the capability of configuring various modes of operation such as boot device, output pad strength,
clock mode options, and chip select configuration.
Freescale Semiconductor
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MD5 one way 128-bit hash function specified in RFC 1321
SHA-1 one way 160-bit hash function specified by the ANSI X9.30-2 and FIPS 180-1 standards
HMAC support for all algorithms, as specified in RFC 2104
EHMAC support for the SHA-1 algorithm
EHMAC key support up to 160 bits
Processes 512 bit blocks organized as 16×32 bit longwords
Automatic message and key padding
Internal 16×32 bit FIFO for temporary storage of hashing data
Operating Modes
DMA Timers
Message Digest Hardware Accelerator (MDHA) Features
Random Number Generator (RNG)
Migrating from the MC68332 to the ColdFire
®
MCF523x, Rev. 1.0
Device Differences
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