TC1796
Peripheral Units (Vol. 2 of 2)
Synchronous Serial Interface (SSC)
User’s Manual
20-52
V2.0, 2007-07
SSC, V2.1
Note: Further details of the fractional divider register functionality are described in
section
“Fractional Divider Operation” on Page 3-29
of the TC1796 User’s
Manual System Units part (Volume 1).
20.3.2.2 Port Control
The interconnections between the SSC modules and the I/O lines/pins are controlled by:
•
Hardware signals of the module kernel for SSC0
•
Software in the port logic for SSC1
The
SSC0
is directly connected to dedicated class A2 pins. Bit SSC0_CON.EN
enables/disables the dedicated pins (signal “SSC Enabled”). After a reset,
SSC0_CON.EN is 0 and the dedicated SSC0 I/O pins are tri-stated. With
SSC0_CON.EN = 1, the dedicated SSC0 I/O pins are enabled and the state of
SSC0_CON.MS (signal “M/S Enabled”) determines whether they act as input or output.
When the SSC0 is enabled (SSC0_CON.EN = 1), changing of SSC0_CON.MS directly
affects the I/O direction of the three SSC0 communication I/O pins.
Note: The dedicated SSC0 output pins do not provide open-drain capability.
The
SSC1
I/O functionality must be selected by the following port control operations
(additionally to the PISEL programming):
•
Input/output function selection (IOCR registers)
•
Pad driver characteristics selection for the outputs (PDR registers)
The SSC1 port input/output control registers contain the bit fields that select the digital
output and input driver characteristics such as pull-up/down devices, port direction
(input/output), open-drain, and alternate output selections. The master/slave I/O lines
and the slave select input of the SSC1 module are class A2 GPIO pins that are controlled
by a port input/output control register of Port 6.
Each of the six
SLSOx
outputs of SSC0 and SSC1 is wired as alternate function to six
class A2 GPIO pins of Port 2 (P2.[7:2]). Two SLSOx outputs with identical index “x” (not
the case for P2.0 and P2.1) are always connected to one I/O line of Port 2, and can be
SUSREQ
29
rh
Suspend Mode Request
Indicates state of SPND signal.
ENHW
30
rw
Enable Hardware Clock Control
Controls operation of ECEN input and DISCLK bit.
DISCLK
31
rwh
Disable Clock
Hardware-controlled disable for
f
OUT
signal.
0
10,
[27:26]
rw
Reserved
Read as 0; should be written with 0.
Field
Bits
Type Description