Chapter 10 XGATE (S12XGATEV3)
MC9S12XE-Family Reference Manual , Rev. 1.19
366
Freescale Semiconductor
NOTE
The XGATE channel IDs that are associated with the eight software triggers
are determined on chip integration level. (see Section “Interrupts“ of the
device overview
)
XGATE software triggers work like any peripheral interrupt. They can be
used as XGATE requests as well as S12X_CPU interrupts. The target of the
software trigger must be selected in the S12X_INT module.
10.3.1.10 XGATE Semaphore Register (XGSEM)
The XGATE provides a set of eight hardware semaphores that can be shared between the S12X_CPU and
the XGATE RISC core. Each semaphore can either be unlocked, locked by the S12X_CPU or locked by
the RISC core. The RISC core is able to lock and unlock a semaphore through its SSEM and CSEM
instructions. The S12X_CPU has access to the semaphores through the XGATE Semaphore Register
(
). Refer to section
for details.
Read: Anytime
Write: Anytime (see
)
Table 10-11. XGSWT Field Descriptions
Field
Description
15–8
XGSWTM[7:0]
Software Trigger Mask
— These bits control the write access to the XGSWT bits. Each XGSWT bit can only
be written if a "1" is written to the corresponding XGSWTM bit in the same access.
Read:
These bits will always read "0".
Write:
0 Disable write access to the XGSWT in the same bus cycle
1 Enable write access to the corresponding XGSWT bit in the same bus cycle
7–0
XGSWT[7:0]
Software Trigger Bits
— These bits act as interrupt flags that are able to trigger XGATE software channels.
They can only be set and cleared by software.
Read:
0 No software trigger pending
1 Software trigger pending if the XGIE bit is set
Write:
0 Clear Software Trigger
1 Set Software Trigger
Module Base +0x0001A
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
R
0
0
0
0
0
0
0
0
XGSEM[7:0]
W
XGSEMM[7:0]
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 10-12. XGATE Semaphore Register (XGSEM)
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