TCC720 Datasheet, PDF (121/143 Pages) List of Unclassifed Manufacturers – 32-bit RISC Microprocessor For Digital Media Player

TCC720
MEMORY CONTROLLER
32-bit RISC Microprocessor for Digital Media Player
Dec. 16. 2002
Preliminary Spec 0.51
13.3 Miscellaneous Configuration
In this register, there is various special flag for TCC720 system.
One of them is for supporting boot PROM. In initialization, the lower address space
(0x00000000 ~ 0x0FFFFFFF) is mapped to internal or external boot ROM but after initialization,
a kind of RAM must be mapped to these space as the system program including interrupt vector
table is located in this area. To satisfy this requirement, TCC720 provide RM flag.
BM flag is used to select the boot procedure between the 7 kinds of them. Refer to chapter of
boot mode for details. BM flag is determined at the rising edge of the nRESET pin, and contains
the state of GPIO_A[10:8] pin.
BW flag is used to know the initial system bus width configuration. This flag is read-only, and
contains the state of GPIO_A[5:4] pin at the rising edge of nRESET pin. So user can control the
bus width by pulling up or down the GPIO_A[5:4] pin.
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