tc94a48fg TOSHIBA Semiconductor CORPORATION, tc94a48fg Datasheet - Page 14

• Manufacturer Part Number: tc94a48fg
• Description: Single-chip Audio Digital Signal Processor Single-chip Audio Digital Signal Processor
• Manufacturer: TOSHIBA Semiconductor CORPORATION

/MICS
/MIACK
/MILP
/MICK
/MIDIO
2.1
2.1.1 Data Transfer Format in Normal Transmission Mode
2.1.2
(1)
Figure 1 shows the data transfer format in normal transmission mode.
In normal transmission mode, the system first drives /MICS low and then checks that /MIACK is low
before transferring a 24-bit command MSB first. It cannot transfer data if /MIACK is high.
The system then reads or writes as many 24-bit data words (one to eight) as specified with the 24-bit
command and finally drives /MICS high. For a read, it should also make sure that /MIACK is low
after transferring a 24-bit command because /MIACK becomes high temporarily after the command is
transferred.
Program boot and program start
The TC94A48FG has 1k-word RAM assigned to program addresses 000h to 3FFh, in which 000h to
003h are interrupt vector addresses. To enable the TC94A48FG to operate, a program must be booted
to an interrupt vector address. If you want to store a program in the area from 004h to 3FFh, a
program loading process must follow the interrupt vector address. For a program boot, the 24-bit
command transferred upon a reset must have the program RAM boot start bit and soft reset bit set to
"1" (command = xxxx60h).
The command must be followed by 16-bit program data, set in lower bits in 24-bit data.
The write address is automatically incremented (by one) from the command (000h). The program boot
completes once /MICS is driven high upon transferring the required number of words.
The write address for a program boot always starts from the command (000h). To start the program,
transfer a 24-bit command with the soft reset
transferring data.
Figure 6 shows the program boot and program start procedure.
Normal Transmission Mode
Data Transfer Method in Normal Transmission Mode
Figure 5(a) Data Transfer Format in Normal Transmission Mode
COMMAND(24bit)
DATA(24bit)
14
bit cleared and then drive /MICS high without
24bit DATA(1～8word)
DATA(24bit)
TC94A48FG
2005-09-28