XC2200 Derivatives
System Units (Vol. 1 of 2)
Interrupt and Trap Functions
User’s Manual
5-44
V2.1, 2008-08
ICU_X2K, V2.2
TFR
Trap Flag Register
SFR (FFAC
H
/D6
H
)
Reset Value: 0000
H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
SR0
STK
OF
STK
UF
SOF
T
BRK
SR1
-
-
-
UND
OPC
-
-
AC
ER
PRT
FLT
ILL
OPA
-
-
rwh rwh rwh rwh rwh
-
-
-
rwh
-
-
rwh rwh rwh
-
-
Field
Bits
Type
Description
SR0
15
rwh
System Request 0 Flag
0
B
No trigger detected
1
B
The selected condition has been detected
STKOF
14
rwh
Stack Overflow Flag
0
B
No stack overflow event detected
1
B
The current stack pointer value falls below the
contents of register STKOV
STKUF
13
rwh
Stack Underflow Flag
0
B
No stack underflow event detected
1
B
The current stack pointer value exceeds the
contents of register STKUN
SOFTBRK
12
rwh
Software Break
0
B
No software break event detected
1
B
Software break event detected
SR1
11
rwh
System Request 1 Flag
0
B
No trigger detected
1
B
The selected condition has been detected
UNDOPC
7
rwh
Undefined Opcode
0
B
No undefined opcode event detected
1
B
The currently decoded instruction has no valid
XC2200 opcode
ACER
4
rwh
Memory Access Error
0
B
No access error event detected
1
B
Illegal or erroneous access detected
PRTFLT
3
rwh
Protection Fault
0
B
No protection fault event detected
1
B
A protected instruction with an illegal format
has been detected