MC68HC705C Motorola, MC68HC705C Datasheet - Page 143

• Manufacturer Part Number: MC68HC705C
• Description: HCMOS Microcontroller Unit
• Manufacturer: Motorola

11.5 Multiple-SPI Systems
MC68HC705C8A — Rev. 2.0
MOTOROLA
Example:
In a multiple-SPI system, all PD4/SCK pins are connected together, all
PD3/MOSI pins are connected together, and all PD2/MISO pins are
connected together.
Before a transmission, one SPI is configured as master and the rest are
configured as slaves.
master SPI and three slave SPIs.
Figure 11-5
three slave SPIs.
LDA #$1C
STA SPCR
LDA #$4C
STA SPCR
Figure 11-4. One Master and Three Slaves Block Diagram
MASTER MCU
Serial Peripheral Interface (SPI)
PD2/MISO
PD3/MOSI
PORT
PD4/SCK
is another block diagram with two master/slave SPIs and
I/O
PD5/SS
; MSTR = 1, CPOL = 1, CPHA = 1,
; SPR1 = SPR0 = 0
; SPI control register
; MSTR = 0, SPE = 1, CPOL = 1, CPHA = 1,
; SPR1 = SPR0 = 0
; SPI control register
2
1
0
Figure 11-4
V
DD
SLAVE MCU 2
is a block diagram showing a single
SLAVE MCU 1
Serial Peripheral Interface (SPI)
SLAVE MCU 0
Multiple-SPI Systems
Technical Data
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