Serial Peripheral Interface (SPI)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor
38-3
38.3
Configuring the SPI Controller
The SPI can be programmed to work in a single- or multiple-master environment. This section describes
SPI master and slave operation in a single-master configuration and then discusses the multi-master
environment.
38.3.1
The SPI as a Master Device
In master mode, the SPI sends a message to the slave peripheral, which sends back a simultaneous reply.
A single master PowerQUICC II with multiple slaves can use general-purpose parallel I/O signals to
selectively enable slaves, as shown in
Figure 38-2
. To eliminate the multimaster error in a single-master
environment, the master’s SPISEL input can be forced inactive by selecting port D[19] for general-purpose
I/O (PDPAR[DD19] = 0).
Figure 38-2. Single-Master/Multi-Slave Configuration
To start exchanging data, the core writes the data to be sent into a buffer, configures a TxBD with TxBD[R]
set, and configures one or more RxBDs. The core then sets SPCOM[STR] in the SPI command register to
start sending data, which starts once the SDMA channel loads the Tx FIFO with data.
The SPI then generates programmable clock pulses on SPICLK for each character and simultaneously
shifts Tx data out on SPIMOSI and Rx data in on SPIMISO. Received data is written into a Rx buffer using
the next available RxBD. The SPI keeps sending and receiving characters until the whole buffer is sent or
an error occurs. The CP then clears TxBD[R] and RxBD[E] and issues a maskable interrupt to the interrupt
controller in the SIU.
SPIMOSI
SPIMISO
SPICLK
SPISEL
Slave 0
SPIMISO
SPICLK
SPISEL
Slave 1
Slave 2
Master SPI
SPIMOSI
SPIMISO
SPICLK
SPISEL
SPIMOSI
The SPISEL
SPICLK
SPIMISO
SPIMOSI
PowerQUICC II
decoder can be
either internal or
external logic.
Содержание MPC8250
Страница 90: ...MPC8260 PowerQUICC II Family Reference Manual Rev 2 lxxxviii Freescale Semiconductor...
Страница 94: ...MPC8260 PowerQUICC II Family Reference Manual Rev 2 I 4 Freescale Semiconductor...
Страница 118: ...Overview MPC8260 PowerQUICC II Family Reference Manual Rev 2 1 24 Freescale Semiconductor...
Страница 236: ...Reset MPC8260 PowerQUICC II Family Reference Manual Rev 2 5 14 Freescale Semiconductor...
Страница 274: ...60x Signals MPC8260 PowerQUICC II Family Reference Manual Rev 2 7 18 Freescale Semiconductor...
Страница 540: ...IEEE 1149 1 Test Access Port MPC8260 PowerQUICC II Family Reference Manual Rev 2 13 8 Freescale Semiconductor...
Страница 548: ...MPC8260 PowerQUICC II Family Reference Manual Rev 2 IV 8 Freescale Semiconductor...
Страница 704: ...Serial Communications Controllers SCCs MPC8260 PowerQUICC II Family Reference Manual Rev 2 20 26 Freescale Semiconductor...
Страница 770: ...SCC BISYNC Mode MPC8260 PowerQUICC II Family Reference Manual Rev 2 23 20 Freescale Semiconductor...
Страница 808: ...SCC Ethernet Mode MPC8260 PowerQUICC II Family Reference Manual Rev 2 25 24 Freescale Semiconductor...
Страница 848: ...Serial Management Controllers SMCs MPC8260 PowerQUICC II Family Reference Manual Rev 2 27 36 Freescale Semiconductor...
Страница 972: ...ATM Controller and AAL0 AAL1 and AAL5 MPC8260 PowerQUICC II Family Reference Manual Rev 2 30 52 Freescale Semiconductor...
Страница 1062: ...ATM AAL1 Circuit Emulation Service MPC8260 PowerQUICC II Family Reference Manual Rev 2 31 46 Freescale Semiconductor...
Страница 1072: ...ATM AAL2 MPC8260 PowerQUICC II Family Reference Manual Rev 2 32 10 Freescale Semiconductor...
Страница 1122: ...Inverse Multiplexing for ATM IMA MPC8260 PowerQUICC II Family Reference Manual Rev 2 33 20 Freescale Semiconductor...
Страница 1178: ...Inverse Multiplexing for ATM IMA MPC8260 PowerQUICC II Family Reference Manual Rev 2 33 76 Freescale Semiconductor...
Страница 1224: ...Fast Ethernet Controller MPC8260 PowerQUICC II Family Reference Manual Rev 2 35 28 Freescale Semiconductor...
Страница 1242: ...FCC HDLC Controller MPC8260 PowerQUICC II Family Reference Manual Rev 2 36 18 Freescale Semiconductor...
Страница 1302: ...Register Quick Reference Guide MPC8260 PowerQUICC II Family Reference Manual Rev 2 A 4 Freescale Semiconductor...
Страница 1318: ...Reference Manual Rev 1 Errata MPC8260 PowerQUICC II Family Reference Manual Rev 2 B 16 Freescale Semiconductor...
Страница 1356: ...MPC8260 PowerQUICC II Family Reference Manual Rev 2 Index 28 Freescale Semiconductor U U Index...