Setup Example - Panasonic F77G User Manual

Chapter 12 Serial Interface 3
13-3-2

Setup Example

Transmission/Reception Setup Example
Here is the setup example for transmission/reception with serial interface 3. Table 12-3-10 shows the
conditions.
Table 12-3-10 Setup conditions for Synchronous Serial Interface Transmission/Reception
Item
SBI3/SBO3 pin
Transfer bit count
Start condition
First bit to be transfered
Input edge
Output edge
An example setup procedure, with a description of each step is shown below.
Setup Procedure
(1) Select prescaler operation.
PSCMD (x'3F6F')
bp0 : PSCEN = 1
(2) Select the clock source.
SC3CKS (x'3FAF')
bp2-0 : SC2PSC2-0 = 100
bp3 = 0
(3) Control the pin type.
SC3ODC (x'3FAE')
bp1-0 : SC3ODC1-0 = 11
P5PLU (x'3F45')
bp2, 1 : P5PLU2, 1 = 1, 1
(4) Control the pin direction.
P5DIR (x'3F35')
bp2-0 : P5DIR2-0 = 110
(5) Select the communication type.
SC3CTR (x'3FAA')
bp2 : SC3CMD = 0
XII - 24
Operation
Set to
independent (with 3 lines) Clock
8 bits
enable
MSB
at falling
at rising
(1)
(2)
(3)
(4)
(5)
Item
Clock source
SBT3/SBO3 pin type
Pull-up resistance of SBT3 pin added
Pull-up resistance of SBO3 pin added
Description
Set the PSCEN flag of the PSCMD register to
"1" to select prescaler operation.
Set the SC3PSC2-0 flag of the SC3CKS register
to "100" to select fs/2 at clock source.
Set bp3 of the SC3CKS register to "0", always.
Set the SC3ODC1-0 flag of the SC3ODC register
to "11" to select N-ch open drain for the SBO3/
SBT3 pin's type. Set the P5PLU2-1 flag of the
P5PLU register to "1, 1" to add pull-up resistor.
Set the P5DIR2-0 flag of P5 pin control direction
register (P5DIR) to "110" to set P52, P51, to
output mode, to set P50 to input mode.
Set the SC3CMD flag of the serial 3 control
register (SC3CTR) to "0" to select synchronous
serial.
Set to
internal clock
fs/2
N-ch open-drain