Intel 81342 Developer's Manual page 812

1 2 . 3 T i m e r S t a t e D i a g r a m
F i g u r e 1 1 7
S e c t i o n 1 2 . 5 , " U n c o m m o n T C R X a n d T R R X C o n d i t i o n s " o n p a g e 8 2 0
F i g u r e 1 1 7 . T i m e r U n i t S t a t e D i a g r a m
®
I n t e l 8 1 3 4 1 a n d 8 1 3 4 2 I / O P r o c e s s o r s
D e v e l o p e r ' s M a n u a l
8 1 2
s h o w s t h e c o m m o n s t a t e s o f t h e T i m e r U n i t . F o r u n c o m m o n c o n d i t i o n s s e e
SW Write
(TMRx.enable = 0)
SW Read
SW Write
TMRx.enable = 1
TMRx.reload = user value
TMRx.pri = user value
TMRx.enable = 0
TMRx.csel1:0 = user value
SW Read
TC = 0
Hardware / Software
Reset
TMRx.enable = 0
TMRx.reload = 0
TMRx.pri = 0
TMRx.csel1:0 = 0
IPND.tip = 0
IDLE
Bus Clock or SW Read
SW Write (TMRx.enable = 1
TMRx.enable = 1
TMRx.reload = user value
TMRx.pri = user value
TMRx.csel1:0 = user value
TCRx=0
Initial TCRx Check
TCRx != 0
Decrement
Clock Unit Tick
TCRx
and TCRx != 0
TCRx = 0
TC = 1
IPND.tip = 1
TMRx.enable = 0
SW Write
SW Read/Write & Reload = 0
®
I n t e l 8 1 3 4 1 a n d 8 1 3 4 2 — T i m e r s
.
"Uncommon TCRX and
TRRX Conditions"
TC = 0
TMRx.enable = 1
TCRx = TRRx
Reload = 1
TC Detected
State
Bus Clock
A6770-01
D e c e m b e r 2 0 0 7
O r d e r N u m b e r : 3 1 5 0 3 7 - 0 0 2 U S