MC68MH360EM33L Freescale Semiconductor, MC68MH360EM33L Datasheet - Page 316

• Manufacturer Part Number: MC68MH360EM33L
• Description: IC MPU QUICC ETHER 33MHZ 240FQFP
• Manufacturer: Freescale Semiconductor

Specifications of MC68MH360EM33L

• Processor Type: M683xx 32-Bit
• Speed: 33MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 240-FQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -

System Integration Module (SIM60)
BACK40—Burst Acknowledge MC68EC040
TRLXQ—Timing Relax
FC3–FC0—Function Code
BA31–BA11—Base Address
6-72
This bit is used to acknowledge a burst cycle to the MC68040. If set, bursts are enabled
in this bank. The QUICC generates address lines 2,3 on the BADDR3–BADDR2 pins.
This bit delays the beginning of the internal QUICC or external QUICC/MC68030-type bus
master cycle to relax the timing constraints on the user. This attribute is useful for slow
peripherals that require additional address setup time. Chip selects are delayed by one
phase, and the cycle is delayed by one clock. For accesses to DRAM, RAS is delayed by
one phase, and CAS and AMUX are delayed by two phases, giving a total cycle increase
of one clock. See Figures 6-16 and 6-17 for timing diagrams of different cases.
This field can be used to specify that accesses with the memory bank be limited to a cer-
tain address space type. These bits are used in conjunction with the FCM3–FCM0 bits in
the OR.
The base address field, the upper 21 bits of each BR, and the function code field are com-
pared to the address on the address bus to determine if a DRAM/SRAM region is being
accessed by an internal QUICC master.
If the SRAM/DRAM region is being accessed by an external master and the WE lines are
not used, then A31–A28 address lines and the BA31–BA28 bits are also used in the com-
parison. If, however, the SRAM/DRAM region is being accessed by an external master
0 = Do not acknowledge burst.
1 = Acknowledge burst; MC68040 bursts are handled by the memory controller for this
0 = Do not relax timing.
1 = Relax timing at the beginning of the cycle. One additional clock cycle is added
bank.
when this bit is set.
CSNT40 is ignored for an SRAM cycle by an external master if
the SYNC bit is cleared. CSNT40 = 1 is not valid for external
DSACK assertion
TRLXQ is ignored for an SRAM cycle by an external master if
the SYNC bit is cleared.
To relax the MC68EC040 cycles, use the TSS40 bit in the GMR.
User should avoid setting both TRLXQ and CSNTQ = 1, when
TCYC = 0. This bit combination will result in a bus cycle without
CS assertion.
Freescale Semiconductor, Inc.
For More Information On This Product,
MC68360 USER’S MANUAL
Go to: www.freescale.com
NOTE
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MOTOROLA