TIMER/COUNTER UNIT
9-4
Figure 9-3. Timers 0 and 1 Flow Chart
Timer
Enabled
(EN = 1)
?
Clear Count
Register
Start
No
Yes
No
Yes
Lo to Hi
transition on input
pin since last
service
?
Done
External
Clocking
(EXT = 1)
?
Retrigger
(RTG = 1)
?
Yes
No
No
Yes
Yes
Did Timer 2
Reach Maxcount
Last Service
State
?
Prescaler On
(P = 1)
?
Lo to Hi
transition on input
pin since last
service
?
Timer Input
at High Level
?
No
No
Yes
Done
Done
Increment
Counter
Yes
Continued
"A"
No
Yes
No
A1294-0A
Summary of Contents for 80C186XL
Page 1: ...80C186XL 80C188XL Microprocessor User s Manual...
Page 2: ...80C186XL 80C188XL Microprocessor User s Manual 1995...
Page 18: ...1 Introduction...
Page 19: ......
Page 27: ......
Page 28: ...2 Overview of the 80C186 Family Architecture...
Page 29: ......
Page 79: ......
Page 80: ...3 Bus Interface Unit...
Page 81: ......
Page 127: ......
Page 128: ...4 Peripheral Control Block...
Page 129: ......
Page 137: ......
Page 138: ...5 ClockGenerationand Power Management...
Page 139: ......
Page 154: ...6 Chip Select Unit...
Page 155: ......
Page 178: ...7 Refresh Control Unit...
Page 179: ......
Page 193: ......
Page 194: ...8 Interrupt Control Unit...
Page 195: ......
Page 227: ......
Page 228: ...9 Timer Counter Unit...
Page 229: ......
Page 253: ......
Page 254: ...10 Direct Memory Access Unit...
Page 255: ......
Page 283: ......
Page 284: ...11 Math Coprocessing...
Page 285: ......
Page 302: ...12 ONCE Mode...
Page 303: ......
Page 306: ...A 80C186 Instruction Set Additions and Extensions...
Page 307: ......
Page 318: ...B Input Synchronization...
Page 319: ......
Page 322: ...C Instruction Set Descriptions...
Page 323: ......
Page 371: ......
Page 372: ...D Instruction Set Opcodes and Clock Cycles...
Page 373: ......
Page 396: ...Index...
Page 397: ......