tc9447f TOSHIBA Semiconductor CORPORATION, tc9447f Datasheet - Page 28

• Manufacturer Part Number: tc9447f
• Description: Single-chip Audio Digital Signal Processor
• Manufacturer: TOSHIBA Semiconductor CORPORATION

(3)
(3-1) Self-boot operation at reset
(3-2) Self-boot operation when setting microcontroller
Self-boot operation
Self-boot operations support two modes: one for use at reset and one for setting the microcontroller.
The modes can be used in combination.
To enter this mode, set the BOOT pin to High, then set the RST pin from Low to High.
The 2048 fs period (46.4 ms when fs = 44.1 kHz) after a reset release is a wait period (for
power-on reset). The boot operation starts at the end of this period.
When switching the setting according to the application, specify the start address using the BA
[1:0] pin. At addresses 000h to 002h, set jump addresses.
The data setting speed is one word of SBROM per 1 fs. As up to 1024 words can be set in the
SBROM, the maximum time required for setting the data is half of the wait period.
In this mode, the microcontroller can specify any address and the operation starts from that
address. The BOOT pin can be set to either High or Low. Setting the self-boot ROM start address
using the BOOT command (CMD: 41h) from the microcontroller starts the boot operation with no
wait.
The boot operation when set from the microcontroller is the same as the self-boot operation at
reset except that the boot operation can start from any address.
Table 2 Relationship between fs and wait period
Table 3 Relationship between BA [1:0] pin value
44.1 kHz
32 kHz
48 kHz
BA1
fs
0
0
1
1
BA0
and start address
0
1
0
1
Wait Period
64.0 ms
46.4 ms
42.7 ms
28
Start Address
Boot Time (Maximum)
000h
001h
002h
003h
32.0 ms
23.2 ms
21.3 ms
2002-02-05
TC9447F