XC2700 Datasheet, PDF (49/62 Pages) Infineon Technologies AG – 16/32-Bit Single-Chip Microcontroller

XC2700 Derivatives
XC2000 Family / Alpha Line
Detailed Errata Description
INT_X.H004 SCU Interrupts Enabled After Reset
Following a reset, the SCU interrupts are enabled by default (register SCU_INTDIS =
0000_H). This may lead to interrupt requests being triggered in the SCU immediately,
even before user software has begun to execute. In the SCU, multiple interrupt sources
are `ORed` to a common interrupt node of the CPU interrupt controller. Due to the
“ORing” of multiple interrupt sources, only one interrupt request to the interrupt controller
will be generated if multiple sources at the input of this OR gate are active at the same
time. If user software enables an interrupt in the interrupt controller (SCU_xIC) which
shares the same node as the SCU interrupt request active after reset, it may lead to the
effect of suppressing the intended interrupt source. So, for all SCU interrupt sources
which will not be used, make sure to disable the interrupt source (SCU_INTDIS) and
clear any pending request flags (SCU_xIC.IR) before enabling interrupts in interrupt
controller.
JTAG_X.H001 JTAG Pin Routing
In the current device, the pins connected to the JTAG interface can be selected by
software (write to register DBGPRR). After a reset, the JTAG interface is connected to
position A (see Table 8). If connected to these pins, the debugger will work without any
restrictions.
Table 8
Pin
LQFP-100
23
6
57
28
5
JTAG Position A
Pin
LQFP-144
34
8
82
39
6
Symbol
P5.2
P7.0
P2.9
P5.4
TRST
Signal
TDI_A
TDO_A
TCK_A
TMS_A
TRST
To use other pins for the JTAG interface, the following sequence of steps must be
executed:
• TRST must be high at the rising edge of PORST. Usually debuggers provide that.
• Debuggers must be set to do a so called `hot attach`. This is connecting the
microcontroller without executing a reset.
• Execute a write to DBGPRR register with the desired selection of pins to be used with
one of the first instructions out of Flash.
Errata Sheet
49
V1.7, 2014-10