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UM10375
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2011. All rights reserved.
User manual
Rev. 3 — 14 June 2011
254 of 368
NXP Semiconductors
UM10375
Chapter 14: LPC13xx SSP0/1
14.7.1 SSP Control Register 0
This register controls the basic operation of the SSP controller.
14.7.2 SSP Control Register 1
This register controls certain aspects of the operation of the SSP controller.
Table 243: SSP Control Register 0 (SSP0CR0 - address 0x4004 0000, SSP1CR0 - address
0x4005 8000) bit description
Bit
Symbol
Value
Description
Reset
value
3:0
DSS
Data Size Select. This field controls the number of bits
transferred in each frame. Values 0000-0010 are not
supported and should not be used.
0000
0x3
4-bit transfer
0x4
5-bit transfer
0x5
6-bit transfer
0x6
7-bit transfer
0x7
8-bit transfer
0x8
9-bit transfer
0x9
10-bit transfer
0xA
11-bit transfer
0xB
12-bit transfer
0xC
13-bit transfer
0xD
14-bit transfer
0xE
15-bit transfer
0xF
16-bit transfer
5:4
FRF
Frame Format.
00
0x0
SPI
0x1
TI
0x2
Microwire
0x3
This combination is not supported and should not be used.
6
CPOL
Clock Out Polarity. This bit is only used in SPI mode.
0
0
SSP controller maintains the bus clock low between frames.
1
SSP controller maintains the bus clock high between frames.
7
CPHA
Clock Out Phase. This bit is only used in SPI mode.
0
0
SSP controller captures serial data on the first clock transition
of the frame, that is, the transition
away from
the inter-frame
state of the clock line.
1
SSP controller captures serial data on the second clock
transition of the frame, that is, the transition
back to
the
inter-frame state of the clock line.
15:8
SCR
Serial Clock Rate. The number of prescaler-output clocks per
bit on the bus, minus one. Given that CPSDVSR is the
prescale divider, and the APB clock PCLK clocks the
prescaler, the bit frequency is PCLK / (CPSDVSR
[SCR+1]).
0x00
31:16 -
-
Reserved.
-