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Nxp semiconductors – NXP Semiconductors LPC24XX UM10237 User Manual

Page 550

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UM10237_4

© NXP B.V. 2009. All rights reserved.

User manual

Rev. 04 — 26 August 2009

550 of 792

NXP Semiconductors

UM10237

Chapter 20: LPC24XX SSP interface SSP0/1

6.9 SSPn Interrupt Clear Register (SSP0ICR - 0xE006 8020, SSP1ICR -

0xE003 0020)

Software can write one or more one(s) to this write-only register, to clear the
corresponding interrupt condition(s) in the SSP controller. Note that the other two interrupt
conditions can be cleared by writing or reading the appropriate FIFO, or disabled by
clearing the corresponding bit in SSPnIMSC.

6.10 SSPn DMA Control Register (SSP0DMACR - 0xE006 8024,

SSP1DMACR - 0xE003 0024)

The SSPnDMACR register is the DMA control register.It is a read/write register.

Table 20–480

shows the bit assignments of the SSPnDMACR register.

Table 478: SSPn Masked Interrupt Status register (SSPnMIS -address 0xE006 801C,

SSP1MIS - 0xE003 001C) bit description

Bit

Symbol

Description

Reset Value

0

RORMIS

This bit is 1 if another frame was completely received while the
RxFIFO was full, and this interrupt is enabled.

0

1

RTMIS

This bit is 1 if the Rx FIFO is not empty, has not been read for
a "timeout period", and this interrupt is enabled.

0

2

RXMIS

This bit is 1 if the Rx FIFO is at least half full, and this interrupt
is enabled.

0

3

TXMIS

This bit is 1 if the Tx FIFO is at least half empty, and this
interrupt is enabled.

0

7:4

-

Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.

NA

Table 479: SSPn interrupt Clear Register (SSP0ICR - address 0xE006 8020, SSP1ICR -

0xE003 0020) bit description

Bit

Symbol

Description

Reset Value

0

RORIC

Writing a 1 to this bit clears the “frame was received when
RxFIFO was full” interrupt.

NA

1

RTIC

Writing a 1 to this bit clears the "Rx FIFO was not empty and
has not been read for a timeout period" interrupt.

NA

7:2

-

Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.

NA

Table 480: SSPn DMA Control Register (SSP0DMACR - address 0xE006 8024, SSP1DMACR -

0xE003 0024) bit description

Bit

Symbol

Description

Reset
Value

0

Receive DMA
Enable
(RXDMAE)

When this bit is set to one 1, DMA for the receive FIFO is
enabled, otherwise receive DMA is disabled.

0

1

Transmit DMA
Enable
(TXDMAE)

When this bit is set to one 1, DMA for the transmit FIFO is
enabled, otherwise transmit DMA is disabled

0

15:2

-

Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.

NA