S912XHZ512F1VAG Datasheet, PDF (217/978 Pages) Freescale Semiconductor, Inc – Covers MC9S12XHZ384, MC9S12XHZ256

Chapter 5 XGATE (S12XGATEV2)
Table 5-1. XGMCTL Field Descriptions (Sheet 2 of 3)
Field
Description
11
XGFACTM
XGFACT Mask — This bit controls the write access to the XGFACT bit. The XGFACT bit can only be set or
cleared if a "1" is written to the XGFACTM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGFACT in the same bus cycle
1 Enable write access to the XGFACT in the same bus cycle
9
XGSWEIF Mask — This bit controls the write access to the XGSWEIF bit. The XGSWEIF bit can only be cleared
XGSWEIFM if a "1" is written to the XGSWEIFM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGSWEIF in the same bus cycle
1 Enable write access to the XGSWEIF in the same bus cycle
8
XGIEM
XGIE Mask — This bit controls the write access to the XGIE bit. The XGIE bit can only be set or cleared if a "1"
is written to the XGIEM bit in the same register access.
Read:
This bit will always read "0".
Write:
0 Disable write access to the XGIE in the same bus cycle
1 Enable write access to the XGIE in the same bus cycle
7
XGE
XGATE Module Enable — This bit enables the XGATE module. If the XGATE module is disabled, pending
XGATE requests will be ignored. The thread that is executed by the RISC core while the XGE bit is cleared will
continue to run.
Read:
0 XGATE module is disabled
1 XGATE module is enabled
Write:
0 Disable XGATE module
1 Enable XGATE module
6
XGFRZ
Halt XGATE in Freeze Mode — The XGFRZ bit controls the XGATE operation in Freeze Mode (BDM active).
Read:
0 RISC core operates normally in Freeze (BDM active)
1 RISC core stops in Freeze Mode (BDM active)
Write:
0 Don’t stop RISC core in Freeze Mode (BDM active)
1 Stop RISC core in Freeze Mode (BDM active)
5
XGDBG
XGATE Debug Mode — This bit indicates that the XGATE is in Debug Mode (see Section 5.6, “Debug Mode”).
Debug Mode can be entered by Software Breakpoints (BRK instruction), Tagged or Forced Breakpoints (see
S12X_DBG Section), or by writing a "1" to this bit.
Read:
0 RISC core is not in Debug Mode
1 RISC core is in Debug Mode
Write:
0 Leave Debug Mode
1 Enter Debug Mode
Note: Freeze Mode and Software Error Interrupts have no effect on the XGDBG bit.
MC9S12XHZ512 Data Sheet, Rev. 1.06
Freescale Semiconductor
217