Chapter 20. Bus Operation
20-23
Bus Errors
Figure 20-20. Longword Write Access To 32-Bit Port Terminated with TEA Timing
Clock 1 (C1)
The write cycle starts in C1. During C1, the MCF5272 places valid values on the address
bus (A[22:0]) and the chip select signal.
Clock 2 (C2)
During C2, the MCF5272 drives the data bus, the byte strobes, and R/W.
Clock 3 (C3)
During C3, the selected device detects an error and asserts TEA. At the end of C3 or Cx,
the MCF5272 samples the level of TEA. If it is asserted, the transfer of the longword is
aborted and the transfer terminates.
NOTE:
This example shows TEA being asserted during C3. TEA can
be asserted earlier or later than C3.
NOTE:
If TA is asserted when debug transfer error-acknowledge
(TEA) is asserted, the transfer is terminated with a bus error.
CLKIN
A[22:0]
D[31:0]
OE
R/W
CSn
TEA
BS[3:0]
(H)
C1
C2
C3
Cx
C4
Содержание DigitalDNA ColdFire MCF5272
Страница 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
Страница 38: ...xxxviii MCF5272 User s Manual TABLES Table Number Title Page Number ...
Страница 58: ...1 10 MCF5272 User s Manual MCF5272 Specific Features ...
Страница 90: ...2 42 MCF5272 User s Manual Exception Processing Overview ...
Страница 96: ...3 6 MCF5272 User s Manual MAC Instruction Execution Timings ...
Страница 158: ...5 46 MCF5272 User s Manual Motorola Recommended BDM Pinout ...
Страница 184: ...7 12 MCF5272 User s Manual Interrupt Controller Registers ...
Страница 338: ...13 44 MCF5272 User s Manual Application Examples ...
Страница 414: ...18 6 MCF5272 User s Manual PWM Programming Model ...
Страница 452: ...19 38 MCF5272 User s Manual Power Supply Pins ...
Страница 482: ...20 30 MCF5272 User s Manual Reset Operation ...
Страница 492: ...21 10 MCF5272 User s Manual Non IEEE 1149 1 Operation ...
Страница 548: ...INDEX Index 12 MCF5272 User s Manual ...