Chapter 10 XGATE (S12XGATEV3)
MC9S12XE-Family Reference Manual , Rev. 1.19
Freescale Semiconductor
361
this register to a channel priority level (non-zero value) selects the corresponding Initial Stack Pointer
Registers XGISP74 or XGISP31 (see
).
Read: Anytime
Write: Anytime
10.3.1.5
XGATE Initial Stack Pointer for Interrupt Priorities 7 to 4 (XGISP74)
The XGISP74 register is intended to point to the stack region that is used by XGATE channels of priority
7 to 4. Every time a thread of such priority is started, RISC core register R7 will be initialized with the
content of XGISP74.
Read: Anytime
Write: Only if XGATE requests are disabled (XGE = 0) and idle (XGCHID = $00))
Module Base +0x0005
7
6
5
4
3
2
1
0
R
0
0
0
0
0
0
XGISPSEL[1:0]
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 10-6. XGATE Initial Stack Pointer Select Register (XGISPSEL)
Table 10-5. XGISPSEL Field Descriptions
Field
Description
1-0
XGISPSEL[1:0]
Register select
— Determines whether XGISP74, XGISP31, or XGVBR is mapped to “Module Base +0x0006”.
See
Table 10-6. XGISP74, XGISP31, XGVBR Mapping
XGISPSEL[1:0]
Register Mapped to “Module Base +0x0006“
3
Reserved
2
XGISP74
1
XGISP31
0
XGVBR
Module Base +0x0006
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
XGISP74[15:1]
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 10-7. XGATE Initial Stack Pointer for Interrupt Priorities 7 to 4 (XGISP74)
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages
