COP888GW Datasheet, PDF (6/44 Pages) National Semiconductor (TI) – 8-Bit Microcontroller with Pulse Train Generators

Pin Descriptions
V_CC and GND are the power supply pins All V_CC and GND
pins must be connected
CKI is the clock input This comes from an R C generated
oscillator or a crystal oscillator (in conjunction with CKO)
See Oscillator Description section
RESET is the master reset input See Reset description
section
The device contains five bidirectional 8-bit I O ports (C E
F G and L) where each individual bit may be independently
configured as an input (Schmitt trigger inputs on ports L and
G) output or TRI-STATE under program control Three data
memory address locations are allocated for each of these
I O ports Each I O port has two associated 8-bit memory
mapped registers the CONFIGURATION register and the
output DATA register A memory mapped address is also
reserved for the input pins of each I O port (See the memo-
ry map for the various addresses associated with the I O
ports ) Figure 3 shows the I O port configurations The
DATA and CONFIGURATION registers allow for each port
bit to be individually configured under software control as
shown below
Configuration Data
Register Register
Port Set-Up
0
0
Hi-Z Input (TRI-STATE Output)
0
1
Input with Weak Pull-Up
1
0
Push-Pull Zero Output
1
1
Push-Pull One Output
PORT L is an 8-bit I O port All L-pins have Schmitt triggers
on the inputs
The Port L supports Multi-Input Wake Up on all eight pins
L1 is used for the UART external clock L2 and L3 are used
for the UART transmit and receive L4 and L5 are used for
the timer input functions T2A and T2B L6 and L7 are used
for the capture timer input functions CAP1 and CAP2
The Port L has the following alternate features
L0 MIWU
L1 MIWU or CKX
L2 MIWU or TDX
L3 MIWU or RDX
L4 MIWU or T2A
L5 MIWU or T2B
L6 MIWU or CAP1
L7 MIWU or CAP2
Port G is an 8-bit port with 6 I O pins (G0 – G5) an input pin
(G6) and a dedicated output pin (G7) Pins G0 – G6 all have
Schmitt Triggers on their inputs Pin G7 serves as the dedi-
cated output pin for the CKO clock output There are two
registers associated with the G Port a data register and a
configuration register Therefore each of the 6 I O bits
(G0 – G5) can be individually configured under software con-
trol
FIGURE 3 I O Port Configurations
TL DD 12065 – 4
http www national com
6