8XC51FX Datasheet, PDF (7/20 Pages) Intel Corporation – CHMOS SINGLE-CHIP 8-BIT MICROCONTROLLERS

8XC51FX
ONCE MODE
The ONCE (‘‘On-Circuit Emulation’’) Mode facilitates
testing and debugging of systems using the
8XC51FX without the 8XC51FX having to be re-
moved from the circuit The ONCE Mode is invoked
by
1) Pull ALE low while the device is in reset and
PSEN is high
2) Hold ALE low as RST is deactivated
While the device is in ONCE Mode the Port 0 pins
float and the other port pins and ALE and PSEN are
weakly pulled high The oscillator circuit remains ac-
tive While the 8XC51FX is in this mode an emulator
or test CPU can be used to drive the circuit Normal
operation is restored when a normal reset is applied
designed to meet the needs of those applications
whose operating requirements exceed commercial
standards
The EXPRESS program includes the commercial
standard temperature range with burn-in and an ex-
tended temperature range with or without burn-in
With the commercial standard temperature range
operational characteristics are guaranteed over the
temperature range of 0 C to 70 C With the extend-
ed temperature range option operational character-
istics are guaranteed over the range of ^b40 C to
a_{85 C}
The optional burn-in is dynamic for a minimum time
of 168 hours at 125 C with V_CC ^e 6 9V g 0 25V
following guidelines in MlL-STD-883 Method 1015
8XC51FX EXPRESS
The Intel EXPRESS system offers enhancements to
the operational specifications of the MCS-51 family
of microcontrollers These EXPRESS products are
Package types and EXPRESS versions are identified
by a one- or two-letter prefix to the part number The
prefixes are listed in Table 3
For the extended temperature range option this
data sheet specifies the parameters which deviate
from their commercial temperature range limits
Table 3 Prefix Identification
Prefix
D
N
P
S
LD
LN
LP
LS
TD
TN
TP
TS
Package Type
Cerdip
PLCC
Plastic
QFP
Cerdip
PLCC
Plastic
QFP
Cerdip
PLCC
Plastic
QFP
Temperature Range
Commercial
Commercial
Commercial
Commercial
Extended
Extended
Extended
Extended
Extended
Extended
Extended
Extended
Burn-In
No
No
No
No
Yes
Yes
Yes
Yes
No
No
No
No
NOTE
Contact distributor or local sales office to match EXPRESS prefix with proper device
EXAMPLES
P87C51FC indicates 87C51FC in a plastic package and specified for commercial temperature range without burn-in
LD87C51FC indicates 87C51FC in a cerdip package and specified for extended temperature range with burn-in
7