DS87C550 EPROM High-Speed Microcontroller with ADC and PWM
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tMCS TIME PERIODS
System Clock Selection
tMCS
4X/ 2X , CD1, CD0 = 100
1 tCLCL
4X/ 2X , CD1, CD0 = 000
2 tCLCL
4X/ 2X , CD1, CD0 = x10
4 tCLCL
4X/ 2X , CD1, CD0 = x11
1024 tCLCL
RD
, WR PULSE WIDTH WITH STRETCH CYCLES
RD
, WR Pulse Width (in oscillator clocks)
MD2
MD1
MD0
MOVX
Machine
Cycles
4X/ 2X =1
CD1:0=00
4X/ 2X =0
CD1:0=00
4X/ 2X =x
CD1:0=10
4X/ 2X =x
CD1:0=11
0
2
0.5 tCLCL
1 tCLCL
2 tCLCL
2048 tCLCL
0
1
3
tCLCL
2 tCLCL
4 tCLCL
4096 tCLCL
0
1
0
4
2 tCLCL
4 tCLCL
8 tCLCL
8192 tCLCL
0
1
5
3 tCLCL
6 tCLCL
12 tCLCL
12288 tCLCL
1
0
9
4 tCLCL
8 tCLCL
16 tCLCL
16384 tCLCL
1
0
1
10
5 tCLCL
10 tCLCL
20 tCLCL
20480 tCLCL
1
0
11
6 tCLCL
12 tCLCL
24 tCLCL
24576 tCLCL
1
12
7 tCLCL
14 tCLCL
28 tCLCL
28672 tCLCL
EXTERNAL CLOCK CHARACTERISTICS
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
NOTES
Clock High Time
tCHCX
10
ns
Clock Low Time
tCLCX
10
ns
Clock Rise Time
tCLCL
5
ns
Clock Fall Time
tCHCL
5
ns
SERIAL PORT MODE 0 TIMING CHARACTERISTICS
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS NOTES
Serial Port Clock Cycle Time
SM2=0, 12 clocks per cycle
SM2=1, 4 clocks per cycle
tXLXL
12tCLCL
4tCLCL
ns
Output Data Setup to Clock Rising
SM2=0, 12 clocks per cycle
SM2=1, 4 clocks per cycle
tQVXH
12tCLCL
4tCLCL
ns
Output Data Hold from Clock Rising
SM2=0, 12 clocks per cycle
SM2=1, 4 clocks per cycle
tXHQX
12tCLCL
4tCLCL
ns
Input Data Hold from Clock Rising
SM2=0, 12 clocks per cycle
SM2=1, 4 clocks per cycle
tXHDX
12tCLCL
4tCLCL
ns
Clock Rising Edge to Input Data Valid
SM2=0, 12 clocks per cycle
SM2=1, 4 clocks per cycle
tXHDV
12tCLCL
4tCLCL
ns