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Nexus
MPC5566 Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor
25-69
4. The data can then be read from the burst data buffer (read/write access data register) through the
access method outlined in
Section 25.11.11, “ NZ6C3 Register Access via JTAG / OnCE
the Nexus register index of 0xA (refer to
5. Repeat step 3 until all doubleword values are read from the buffer.
NOTE
The data values must be shifted out 32-bits at a time lsb first (that is,
doubleword read = two word reads from the RWD).
NOTE
The actual RWA value as well as the CNT field within the RWCS are not
changed when executing a block read access (burst or non-burst). The
original values can be read by the external development tool at any time.
25.14.8.7 Error Handling
The NZ6C3 module handles various error conditions as follows:
25.14.8.7.1
System Bus Read/Write Error
All address and data errors that occur on read/write accesses to the e200z6 system bus returns a transfer
error. If this occurs:
1. The access is terminated without re-trying (AC bit is cleared).
2. The ERR bit in the RWCS register is set.
3. The error message is sent (TCODE = 8) indicating read/write error.
25.14.8.7.2
Access Termination
The following cases are defined for sequences of the read/write protocol that differ from those described
in the above sections:
1. If the AC bit in the RWCS register is set to start read/write accesses and invalid values are loaded
into the RWD and/or RWA, then a system bus access error may occur. This is handled as described
above.
2. If a block access is in progress (all cycles not completed), and the RWCS register is written, then
the original block access is terminated at the boundary of the nearest completed access.
a) If the RWCS is written with the AC bit set, the next read/write access begins and the RWD can
be written to/ read from.
b) If the RWCS is written with the AC bit cleared, the read/write access is terminated at the nearest
completed access. This method can be used to break (early terminate) block accesses.
25.14.8.8
Read/Write Access Error Message
The read/write access error message is sent out when an system bus access error (read or write) has
occurred.
Summary of Contents for MPC5566
Page 81: ...Introduction MPC5566 Microcontroller Reference Manual Rev 2 1 24 Freescale Semiconductor...
Page 135: ...Signal Description MPC5566 Microcontroller Reference Manual Rev 2 2 54 Freescale Semiconductor...
Page 189: ...Reset MPC5566 Microcontroller Reference Manual Rev 2 4 20 Freescale Semiconductor...
Page 603: ...Flash Memory MPC5566 Microcontroller Reference Manual Rev 2 13 38 Freescale Semiconductor...
Page 609: ...SRAM MPC5566 Microcontroller Reference Manual Rev 2 14 6 Freescale Semiconductor...
Page 1073: ...MPC5566 Microcontroller Reference Manual Rev 2 22 36 Freescale Semiconductor...
Page 1185: ...Nexus MPC5566 Microcontroller Reference Manual Rev 2 25 92 Freescale Semiconductor...