DS5003
Secure Microprocessor Chip
12 ______________________________________________________________________________________
Pin Description
PIN NAME FUNCTION
POWER PINS
13 V
CC
Power Supply, +5V
12 V
CCO
V
CC
Output. This is switched between V
CC
and V
LI
by internal circuits based on the level of V
CC
.
When power is above the lithium input, power is drawn from V
CC
. The lithium cell remains
isolated from a load. When V
CC
is below V
LI
, V
CCO
switches to the V
LI
source. V
CCO
should be
connected to the V
CC
pin of an SRAM.
54 V
LI
Lithium Voltage Input. Connect to a lithium cell greater than V
LIMIN
and no greater than V
LIMAX
as shown in the electrical specifications. Nominal value is +3V.
52 GND Logic Ground
GENERAL-PURPOSE I/O PINS
11 P0.0/AD0
9 P0.1/AD1
7 P0.2/AD2
5 P0.3/AD3
1 P0.4/AD4
79 P0.5/AD5
77 P0.6/AD6
75 P0.7/AD7
General-Purpose I/O Port 0. This port is open drain and cannot drive a logic 1. It requires
external pullups. Port 0 is also the multiplexed expanded address/data bus. When used in this
mode, it does not require pullups.
15 P1.0
17 P1.1
19 P1.2
21 P1.3
25 P1.4
27 P1.5
29 P1.6
31 P1.7
General-Purpose I/O Port 1
49 P2.0/A8
50 P2.1/A9
51 P2.2/A10
56 P2.3/A11
58 P2.4/A12
60 P2.5/A13
64 P2.6/A14
66 P2.7/A15
General-Purpose I/O Port 2. Also serves as the MSB of the expanded address bus.
36 P3.0/RXD
General-Purpose I/O Port Pin 3.0. Also serves as the receive signal for the on-board UART.
This pin should not be connected directly to a PC COM port.
38 P3.1/TXD
General-Purpose I/O Port Pin 3.1. Also serves as the transmit signal for the on-board UART.
This pin should not be connected directly to a PC COM port.
39 P3.2/INT0 General-Purpose I/O Port Pin 3.2. Also serves as the active-low external interrupt 0.
40 P3.3/INT1 General-Purpose I/O Port Pin 3.3. Also serves as the active-low external interrupt 1.
41 P3.4/T0 General-Purpose I/O Port Pin 3.4. Also serves as the timer 0 input.
44 P3.5/T1 General-Purpose I/O Port Pin 3.5. Also serves as the timer 1 input.
45 P3.6/WR General-Purpose I/O Port Pin 3.6. Also serves as the write strobe for expanded bus operation.
46 P3.7/RD General-Purpose I/O Port Pin 3.7. Also serves as the read strobe for expanded bus operation.
