uPSD3234A, uPSD3234BV, uPSD3233B, uPSD3233BV
Port C – Functionality and Structure
Port C can be configured to perform one or more
of the following functions (see Figure
– MCU I/O Mode
– CPLD Output – McellBC7-McellBC0 outputs
can be connected to Port B or Port C.
– CPLD Input – via the Input Macrocells (IMC)
– In-System Programming (ISP) – JTAG pins
(TMS, TCK, TDI, TDO) are dedicated pins for
device programming. (See
for more information
on JTAG programming.)
Figure 66. Port C Structure
DATA OUT
REG.
D
WR
1
OUTPUT
MUX
PORT C PIN
Q
DATA OUT
Open Drain – Port C pins can be configured in
Open Drain Mode
– Battery Backup features – PC2 can be
configured for a battery input supply, Voltage
Stand-by (V
STBY
).
PC4 can be configured as a Battery-on
Indicator (V
BATON
), indicating when V
CC
is
less than V
BAT
.
Port C does not support Address Out Mode, and
therefore no Control Register is required.
–
SPECIAL FUNCTION
MCELLBC [ 7:0 ]
READ MUX
MCU DATA BUS
P
D
B
DATA IN
OUTPUT
SELECT
ENABLE OUT
DIR REG.
D
WR
ENABLE PRODUCT TERM (.OE)
INPUT
MACROCELL
1
CONFIGURATION
BIT
AI06618
Q
CPLD - INPUT
SPECIAL FUNCTION
Note: 1. ISP or battery back-up
125/170
STMICROELECTRONICS [ STMICROELECTRONICS ]
