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2 qspi delay register (qdlyr), 2 qspi delay register (qdlyr) -5 – Motorola ColdFire MCF5281 User Manual

Page 409

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Queued Serial Peripheral Interface (QSPI)

Freescale Semiconductor

22-5

Figure 22-3

shows an example of a QSPI clocking and data transfer.

Figure 22-3. QSPI Clocking and Data Transfer Example

22.3.2

QSPI Delay Register (QDLYR)

The QDLYR is used to initiate master mode transfers and to set various delay parameters.

IPSBAR

Offset:

0x00_0344 (QDLYR)

Access: User read/write

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

R

SPE

QCD

DTL

W

Reset

0

0

0

0

0

1

0

0

0

0

0

0

0

1

0

0

Figure 22-4. QSPI Delay Register (QDLYR)

Table 22-4. QDLYR Field Descriptions

Field

Description

15

SPE

QSPI enable. When set, the QSPI initiates transfers in master mode by executing commands in the command RAM.
The QSPI clears this bit automatically when a transfer completes. The user can also clear this bit to abort transfer
unless QIR[ABRTL] is set. The recommended method for aborting transfers is to set QWR[HALT].

14–8
QCD

QSPI_CLK delay. When the DSCK bit in the command RAM is set this field determines the length of the delay from
assertion of the chip selects to valid QSPI_CLK transition. See

Section 22.4.3, “Transfer Delays”

for information on

setting this bit field.

7–0

DTL

Delay after transfer. When the DT bit in the command RAM is set this field determines the length of delay after the
serial transfer.

QSPI_CLK

QSPI_DOUT

QSPI_DIN

QSPI_CS

A

B

QMR[CPOL] = 0
QMR[CPHA] = 1
QCR[CONT] = 0

Chip selects are active low

A = QDLYR[QCD]
B = QDLYR[DTL]

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

msb

MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3

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