COP404C Datasheet, PDF (17/18 Pages) National Semiconductor (TI) – COP404C ROMless CMOS Microcontrollers

Emulation (Continued)
When AD DATA turns off the EPROM is enabled and the
IP7 – IP0 pins will input the memory data A10 A9 and A8
output the most significant address bits to the memory
(SKIP output may be used for program debug if needed )
CKI is divided by 4 Other divide-by are emulated by ex-
ternal divider
CKO can be emulated as a general purpose input by us-
ing CKOI or as a Halt I O port by using CKOH
MB pin can be pulled low if the MICROBUS feature of the
COP444C and COP424C is needed Othewise it should
be high
DUAL pin can be pulled low if the Dual-Clock feature of
the COP444C and COP424C is needed Otherwise it
should be high
The SEL10 and SEL20 inputs are used to emulate the
COP444C 445C COP424C 425C or COP410C 411C
 When emulating the COP444C 445C the user must
configure SEL20e1 and SEL10e1
 When emulating the COP424C 425C the user must
configure SEL20e0 and SEL10e1 In this mode the
user RAM is physically halved As in the COP424C
425C the user has 64 digits (256 bits) of RAM avail-
able Pin A10 should not be connected to the program
memory (most significant address bit of the program
memory should be grounded if using a 2kc8 memory)
 When emulating the COP410C 411C the user must
configure SEL20e0 and SEL10e0 In this mode the
user has 32 digits (128 bits) of RAM available orga-
nized in the same way as the COP410C 411C - 4 regis-
ters of 8 digits each Pins A10 and A9 should not be
connected to the program memory (the 2 most signifi-
cant address bits of the program memory should be
grounded)
Furthermore the subroutine stack is decreased from 3
levels to 2 levels
The pins SEL10 and SEL20 change the internal logic of the
device to accurately emulate the devices as indicated
above However the user must remember that the
COP424C 425C is a subset of the COP444C COP445C
with respect to memory size The COP410C 411C is a sub-
set both in memory size and in function The user must take
care not to use features and instructions which are not avail-
able on the COP410C 411C (see table IV below) when us-
ing the COP404C to emulate the COP410C 411C
TABLE IV FEATURES AND INSTRUCTIONS NOT
AVAILABLE ON COP410C 411C
Timer
ADT
Dual-clock CASC
Interrupt CAMT
Microbus
CTMA
IT
LDD
rd
XAD
r d (except 3 15)
XABR
SKT
ININ
INIL
OGI
y
Option Table
COP404C MASK OPTIONS
The following COP444C options have been implemented in the COP404C
Option value
Option 1e0
Option 2e1 2
Option 3e5
Option 4e1
Option 5 – 8e0
Option 9e1
Option 10e1
Option 11e0
Option 12 – 15e0
Option 16e1
Option 17e0
Option 18e0
Option 19e1
Option 20e1
Option 21 – 24e1
Option 25 – 28e0
Option 29e1
Option 30e0 1
Option 31e0
Option 32e0 1
Option 33eN A
Comment
Ground Pin no option available
CKO is replaced by CKOI and CKOH
CKI is external clock input divided by 4
RESET is Hi-Z input
L outputs are standard TRI-STATE
IN1 is a Hi-Z input
IN2 is a Hi-Z input
V_CC pin no option available
L outputs are standard TRI-STATE
SI is a Hi-Z input
SO is a standard output
SK is a standard output
IN0 is a Hi-Z input
IN3 is a Hi-Z input
G outputs are low-current
D outputs are standard
No internal initialization logic
DUAL-CLOCK is pin selectable
TIMER time-base counter
MICROBUS is pin selectable
48-pin package
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