TCC76 Datasheet, PDF (227/259 Pages) List of Unclassifed Manufacturers – 32-bit RISC Microprocessor For Digital Media Player

TCC76x
Specification Rev. 0.07
32-bit RISC Microprocessor for Digital Media Player
February 23, 2005
BOOTING PROCEDURE
20 BOOTING PROCEDURE
20.1 Overview
In the TCC76x, there is an internal boot ROM for system initialization process. It
contains the fundamental routines for system initialization or boot procedure through
various interface such as USB, NAND flash, and I2C.
There are 5 modes for booting procedure. Figure 20.1 illustrates the timing of reset
sequence at power-up. During this process, the boot mode is selected by the state of
GPIO_B[24,22,21] at nRESET going to high.
Table 20.1 represents the boot mode of the TCC76x.
VDDI
VDDIO
Xin/Xout
nRESET
GPIO_B
[24,22,21]
internal
reset
tRST
tBS tBH
BM[2:0]
Variable according to the application
2¹⁷ number of Xin clock
tBH
tBS
tRST
: Hold time for boot mode setting. Minimum 10ns
: Setup time for boot mode setting. Minimum 10ns
: Time of reset activation must be maintained during power-up.
Depending upon the stabilization time of crystal oscillator.
Typically about 10us.
Figure 20.1 Reset Sequence
Preliminary
20-1