4-12
MPC106 PCIB/MC User's Manual
MOTOROLA
The MPC106 propagates snoop broadcast operations to the 60x bus in response to PCI bus-
initiated memory accesses. All snoop broadcasts generated by the MPC106 are caused by
PCI bus operations and are identified as burst, cacheable, write-back, and global accesses.
The transaction types driven by the MPC106 for snoop operations are not encoded as
address-only; however, all MPC106-initiated snoop operations should be treated as
address-only transactions, and no DBG
n
or TA signal assertions should be expected
following the address tenure. Table 4-2 describes the transfer type encodings generated by
the MPC106.
0100x
Direct-store load
request
Error
—
Illegal operation; signals error. Address only
operation. AACK is asserted.
10100
Graphic write (
ecowx
)
Error
TEA
asserted
Illegal operation; signals error. AACK is
asserted; TEA will be asserted if enabled. If
TEA is not enabled, data tenure is terminated
by TA.
11100
Graphic read (
eciwx
)
Error
TEA
asserted
Illegal operation; signals error. AACK is
asserted; TEA will be asserted if enabled. If
TEA is not enabled, data tenure is terminated
by TA.
0101x
Direct-store load
immediate
Error
TEA
asserted
Illegal operation; signals error. AACK is
asserted; TEA will be asserted if enabled. If
TEA is not enabled, data tenure is terminated
by TA.
0111x
Direct-store load last
Error
TEA
asserted
Illegal operation; signals error. AACK is
asserted; TEA will be asserted if enabled. If
TEA is not enabled, data tenure is terminated
by TA.
0001x
Direct-store store
immediate
Error
TEA
asserted
Illegal operation; signals error. AACK is
asserted; TEA will be asserted if enabled. If
TEA is not enabled, data tenure is terminated
by TA.
0011x
Direct-store store last
Error
TEA
asserted
Illegal operation; signals error. AACK is
asserted; TEA will be asserted if enabled. If
TEA is not enabled, data tenure is terminated
by TA.
Table 4-1. MPC106 Responses to 60x Transfer Type Signals (Continued)
TT[0–4]
Bus Operation
Class of
Operation
TEA
MPC106 Response