14-2
MCF5272 User’s Manual
Module Description
14.3.1 Interface and Pins
The module provides as many as 15 ports and a total of seven signals: QSPI_Dout,
QSPI_Din, QSPI_CLK, QSPI_CS0, QSPI_CS1, QSPI_CS2, and QSPI_CS3.
Peripheral chip-select signals, QSPI_CS[0:3], are used to select an external device as the
source or destination for serial data transfer. Signals are asserted at a logic level
corresponding to the value of the QSPI_CS[3:0] bits in the command RAM whenever a
command in the queue is executed. More than one chip-select signal can be asserted
simultaneously.
Although QSPI_CS[0:3] will function as simple chip selects in most applications, up to 15
ports can be selected by decoding them with an external 4-to-16 decoder.
Figure 14-1. QSPI Block Diagram
Note that chip selects QSPI_CS[3:1] are multiplexed with other pin functions. QSPI_Dout,
QSPI_CLK, and QSPI_CS0 are multiplexed with MCF5272 configuration inputs that only
function during system reset.
Queue Control
Block
Queue
Pointer
CLKIN
4
Done
Comparator
End Queue
Pointer
Status
Regs
Delay
Counter
Control Logic
Control
Regs
Address
Register
80-Byte
QSPI
RAM
Chip
Select
Command
Divide by 2
Baud Rate
Generator
MSBit
LSBit
Logic
Array
QSPI_CLK
QSPI_CS[3:0]
QSPI_Din
8/16 Bit Shift Reg.
Rx/Tx Data Reg.
QSPI_Dout
4
4
4
Internal Bus
4
Содержание DigitalDNA ColdFire MCF5272
Страница 1: ...MCF5272UM D Rev 0 02 2001 MCF5272 ColdFire Integrated Microprocessor User s Manual ...
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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 ...