Hey, I have some question about the ordering information of MPC8270 processor. I would like to ask that in this processor "MPC8270CVVQLDA" what does QLD refers to? and can you provide me the difference between 60x and Local Bus of MPC8270 architecture? Th

[talhazubair]

Hey, I have some question about the ordering information of MPC8270 processor. I would like to ask that in this processor "MPC8270CVVQLDA" what does QLD refers to? and can you provide me the difference between 60x and Local Bus of MPC8270 architecture? Thanks 

[talhazubair]

Hey, Thank you! I am using mpc8270 as single master mode, I have interfaced SDRAM with processor as given in reference document of NXP "AN2922". I want to interface a flash of 16 bit with processor and can't decide that should i use 'BADDR[27-31] or A[27-31]. What is the difference between them? I want to connect 4 flash IC of 16-bit data width on processor 64-bit data width (i.e IC 1 on processor(D0-15), IC 2 on Processor(D16-31),IC 3 on Processor(D32-47), IC 2 on Processor(D48-63)).

[alexander_yakov · Accepted solution]

"QLD" encodes Core, CPM and bus maximum frequencies. "Q" means 333 Mhz core, "L" means 250 Mhz CPM, and "D" means 83 Mhz bus.

The processor has two different bus interfaces - 60x bus and local bus. 60x bus is primary bus used for main SDRAM memory connection and for connection of other devices. Local bus is separate bus for connecting SDRAM memory, directly accessible by CPM. Main core accesses this bus via 60x bus to local bus interface, while CPM can access this bus directly, so can perform a direct access even when 60x bus is busy by other transaction. Because of this advantage, local bus is used in designs, where low latency memory is mandatory, for example to store ATM connection tables, as shown in MPC8280 Reference Manual, Section 1.7 "Application Examples".

Unlike other processors, where "local bus" means bus for local memory connection, in MPC82xx family devices local bus should not be used for primary memory, 60x bus must be used.   

Have a great day,
Alexander
TIC

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[talhazubair]

Thank you! It really helps me differentiating Local Bus and 60x bus. Can you recommend me the latest L2 Cache which can be interfaced with mpc8270 as mpc2605 is obsolete. Thanks 

Best Regards 

[alexander_yakov]

Sorry, we do not have ready-to-use suggestion for L2 cache implementation for MPC82xx family.