State 00
00000000
State 01
00000000
State 10
00000000
State 11
00000010
PPUS1=0
PPUS2=0
PPUS1=1
PPUS2=1
PPUS1=0
PPUS2=1
PPUS1=1
PPUS2=0
PPUS1=1
PPUS2=0
PPUS1=1
PPUS2=1
PPUS1=0
PPUS2=0
PPUS1=0
PPUS2=1
PPUS1=0
PPUS2=0
PPUS1=1
PPUS2=0
PPUS1=1
PPUS2=1
PPUS1=0
PPUS2=1
PPUS1=1
PPUS2=0
PPUS1=0
PPUS2=1
PPUS1=1
PPUS2=1
PPUS1=0
PPUS2=0
reset
ESI Operation
984
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
Extended Scan Interface (ESI)
37.2.5.5 Simplest State Machine
shows the simplest state machine that can be realized with the PSM. The following code
shows the corresponding state table.
Figure 37-14. Simplest PSM State Diagram (ESIV2SEL=1)
; Simplest State Machine Example
SIMPLEST_PSM
db 000h ; State 00 (State Table Index 0)
db 000h ; State 01 (State Table Index 1)
db 000h ; State 10 (State Table Index 2)
db 002h ; State 11 (State Table Index 3)
If the PSM is in state 01 of the simplest state machine and the PSM has loaded the corresponding byte at
index 01h of the state table:
Q7
Q6
Q5
Q4
Q3
Q2
Q1
Q0
0
0
0
0
0
0
0
0
For this example, PPUS1 and PPUS2 are set at the end of the next TSM sequence. To calculate the next
state the bits Q5 - Q3 and Q0 of the state 01 table entry, together with the PPUS1 and PPUS2 signals are
combined to form the next state:
V7
V6 (Q6)
V5 (Q5)
V4 (Q4)
V3 (Q3)
V2 (Q0)
V1 (PPUS2)
V0 (PPUS1)
0
0
0
0
0
0
1
1
The state table entry for state 11 is loaded at the next state transition:
V7
V6 (Q6)
V5 (Q5)
V4 (Q4)
V3 (Q3)
V2 (Q0)
V1 (PPUS2)
V0 (PPUS1)
0
0
0
0
0
0
1
0