OM13008,598 NXP Semiconductors, OM13008,598 Datasheet - Page 332

• Manufacturer Part Number: OM13008,598
• Description: BOARD LPC XPRESSO LPC122X
• Manufacturer: NXP Semiconductors
• Series: LPCXpressor

Specifications of OM13008,598

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 568-6642; OM13008

NXP Semiconductors
UM10441
User manual
21.6.10 Channel request mask clear register
21.6.9 Channel request mask set register
Table 328. Channel useburst clear register (CHNL_USEBURST_CLR, address 0x4004 C01C)
This register is a read/write register and disables a HIGH on the DMA request signal for a
channel c (c = 0 to 20) (dma_req[c] signal), or the single DMA request signal
(dma_sreqc[c]), from generating a request. Reading the register returns the request mask
status for dma_req[c] and dma_sreq[c]. Writing to a bit where a DMA channel is not
implemented has no effect.
Table 329. Channel request mask set register (CHNL_REQ_MASK_SET, address 0x4004
This register is a write-only register and for a channel c (c = 0 to 20) enables a HIGH on
dma_req[c], or dma_sreq[c], to generate a request. Writing to a bit where a DMA channel
is not implemented has no effect.
Bit
20:0
31:21
Bit
20:0
31:21 -
Symbol
CHNL_REQ_
MASK_SET
Symbol
CHNL_USEBURST_
CLR
-
bit description
C020) bit description
All information provided in this document is subject to legal disclaimers.
Rev. 1.1 — 10 March 2011
Chapter 21: LPC122x General purpose micro DMA controller
Description
Returns the request mask status of dma_req[c] and
dma_sreq[c], or disables the corresponding channel from
generating DMA requests.
Read as:
Bit [c] = 0: External requests are enabled for channel c.
Bit [c] = 1: External requests are disabled for channel c.
Write as:
Bit [c] = 0: No effect. Use the CHNL_REQ_MASK_CLR
Register to enable DMA requests.
Bit [c] = 1: Disables dma_req[c] and dma_sreq[c] from
generating DMA requests.
Reserved.
Description
Set the appropriate bit to enable dma_sreq[c] to generate
requests. (For channels 4 and 5 only.)
Write as:
Bit [c] = 0: No effect. Use the chnl_useburst_set Register
to disable dma_sreq[c] from generating requests.
Bit [c] = 1: Enables dma_sreq[c] to generate DMA
requests.
Reserved.
UM10441
© NXP B.V. 2011. All rights reserved.
332 of 442
Reset
value
0x0
-
Reset
value
-
-