13-12
MPC565/MPC566 Reference Manual
MOTOROLA
Programming the QADC64E Registers
During freeze, the analog clock, QCLK, is held in reset and the periodic/interval timer is
held in reset. External trigger events that occur during the freeze mode are not captured. The
BIU remains active to allow IMB access to all QADC64E registers and RAM. Although
the QADC64E saves a pointer to the next CCW in the current queue, the software can force
the QADC64E to execute a different CCW by writing new queue operating modes for
normal operation. The QADC64E looks at the queue operating modes, the current queue
pointer, and any pending trigger events to decide which CCW to execute when exiting
freeze.
If the FRZ bit is clear, the internal FREEZE signal is ignored.
13.2.1.3 Supervisor/Unrestricted Address Space
The QADC64E memory map is divided into two segments: supervisor-only data space and
assignable data space. Access to supervisor-only data space is permitted only when the
software is operating in supervisor access mode. Assignable data space can be either
restricted to supervisor-only access or unrestricted to both supervisor and user data space
accesses. The SUPV bit in the QADCMCR designates the assignable space as supervisor
or unrestricted.
The following information applies to accesses to address space located within the modules’
16-bit boundaries and where the response is a bus error. See
Table 13-6 for more
information.
Attempts to read a supervisor-only data space when not in the supervisor access
mode and SUPV = 1, causes the bus master to assert a bus error condition. No data
is returned. If SUPV = 0, the QADC64E asserts a bus error condition and no data is
returned,
Attempts to write supervisor-only when not in the supervisor access mode and
SUPV = 1, causes the bus master to assert a bus error condition. No data is written.
If SUPV = 0, the QADC64E asserts a bus error condition and the register is not
written.
Attempts to read unimplemented data space in the unrestricted access mode and
SUPV = 1, causes the bus master to assert a bus error condition and no data is
returned. In all other attempts to read unimplemented data space, the QADC64E
causes a bus error condition and no data is returned.
Attempts to write unimplemented data space in the unrestricted access mode and
SUPV= 1, causes the bus master to assert a bus error condition and no data is written.
In all other attempts to write unimplemented data space, the QADC64E causes a bus
error condition and no data is written.