Philips Semiconductors
Preliminary specification
80C51 8-bit microcontroller
8K/256 OTP, 8 channel 10 bit A/D, I2C, PWM,
capture/compare, high I/O, low voltage (2.7V–5.5V), low power
P87C552
2.4V
2.0V
0.8V
2.0V
0.8V
Test Points
0.45V
NOTE:
AC inputs during testing are driven at 2.4V for a logic ‘1’ and 0.45V for a logic ‘0’.
Timing measurements are made at 2.0V for a logic ‘1’ and 0.8V for a logic ‘0’.
SU00215
Figure 53. AC Testing Input/Output
Float
2.4V
2.4V
2.0V
0.8V
2.0V
0.8V
0.45V
0.45V
NOTE:
The float state is defined as the point at which a port 0 pin sinks 3.2mA or sources 400µA at the voltage test levels.
SU00216
Figure 54. AC Testing Input, Float Waveform
repeated START condition
START or repeated START condition
START condition
t
SU;STA
STOP condition
t
RD
0.7 V
CC
SDA
(INPUT/OUTPUT)
0.3 V
CC
t
BUF
t
t
t
FC
FD
RC
t
SU;STO
0.7 V
CC
SCL
(INPUT/OUTPUT)
0.3 V
CC
t
SU;DAT3
t
t
t
HIGH
t
SU;DAT1
t
t
SU;DAT2
HD;STA
LOW
HD;DAT
SU00107A
2
Figure 55. Timing SIO1 (I C) Interface
69
1999 Mar 30
NXP [ NXP ]
