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GR716-DS-UM, May 2019, Version 1.29
453
www.cobham.com/gaisler
GR716
45.6.2 Message Header -Response Token
The slave transmits a message header which consist of status of module and details of error occurred.
The message header sent by SPI slave device is called response token which consist of two 16 bit
words. The message header content details are explained below..
Table 606.
Response Token Word #1
MSB
Response Token Word #2
LSB
Prefix
Command Code
Spare
Module State
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
’0’
’1’
SFT
ME
AR
IC
’0’
’0’
’0’
’0’
’0’
’0’
MS3
MS2
MS1
MS0
Table 607.
Response Token Word #3
MS
B
Response Token Word #2
LSB
Prefix
DATA
Spare
CRC-4
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
’0’
’1’
SA7
’0’
’0’
’1’
’1’
’1’
’0’
’0’
’0’
’0’
C3
C2
C1
C0
Table 608.
Response Status bit
Bit
Identifier
Type
Value
Description
Clear Condition
Comment
13
TERMINAL_FAULT Error ’0’ = no fault
‘1’ = fault
The bit flag a SPI
terminal fault condi-
tion.
According to the
module current state.
In SPI slave device
this bit is enabled or
disabled by SPI2
control register
(STF) using APB.
12
MESSAGE_ERROR
Error ’0’ = no fault
‘1’ = fault
This bit is utilized to
indicate that the pre-
vious message
received from the
bus master has failed
to pass the validity
tests.
Always related to
the previous com-
mand. Reception of
a valid command
will clear it (with a
delay of one com-
mand).
This status bit is
enabled when the
received message
fails to pass the
command token and
payload data CRC
checks. The next
valid command
clears this status bit.
11
ADDRESS_ERROR
Error ’0’ = no fault
‘1’ = fault
This bit flag an
AMBA error
occurred while per-
forming the previ-
ous command.
Always related to
the previous com-
mand. Reception of
a valid command
will clear it (with a
delay of one com-
mand)
The SPI slave
device uses an AHB
master to perform
the memory read
and write, this bit is
enabled when an
AHB error is
reported.