17-8
MCF5249UM
MOTOROLA
Serial Audio Interface (IIS/EIAJ)
SIZE
7,6
See notes 3, 4, and 8 following bit these descriptions.
00: 16 bits
01: 18 bits
10: 20 bits
11: zero
MODE
5
1 = Sony, EIAJ mode
0 = Philips IIS mode
LRCK
FREQUENCY
4,.3,2
100: 64 bit clocks / word clock
010: 48 bit clocks / word clock
000: 32 bit clocks / word clock
Other settings: reserved, undefined
LRCK INVERT
1
See note 5 following bit these descriptions.
1 = Invert on word clock
0 = No invert on word clock
SCLK INVERT
0
See note 6following bit these descriptions.
1 = Invert on bit clock
0 = No invert on bit clock
Note:
1. Audio Clk is normally 16.93 MHz. Actual value given
Table 4-4 on page 5. When divided SYSCLOCK is selected as SCLK
output, LRCK will be output too, and is divided from SCLK, using division factor defined by field 4,3,2 - LRCK frequency.
Note:
2. When bit 11 is set, FIFO is in reset condition. The FIFO is always re-set to “1 sample remaining”. The value of the remaining
one sample will be all-zero.
Note:
3. When Philips IIS mode is selected, 16-18-20 bits should yield same result.
Note:
4. Internal interface in MCF5249 is 40 bits / sample (20 left + 20 right). 16, 18 bit words are padded with zeros
Note:
5. LRCK invert will invert the incoming LRCK signal between the pin and the serial data receiver and transmitter
Note:
6. SCLK invert will invert the incoming SCLK signal between the pin and the serial data receiver and transmitter.
Note:
7. Reset to one sample remaining is used to synchronize the data transfer from one input interface to another output interface
running at the same frequency.
Note:
8. “zero” means data is transferred at the sampling frequency, with all data cleared down to digital zero.
Note:
9. PDOR1, PDOR2, PDOR3: ColdFire data out registers.
Note:
10. Serial data transmit / receive interfaces have no limit on minimum incoming or outgoing sampling frequency. The maximum
SCLK frequency is limited to 1/3 of the internal system clock (CPUclk/2). Mark/space ratio should be equal or better than
38/62.
Note:
11. Reprogramming bits 15-12 during functional operation is not allowed. Reprogramming only allowed while FIFO is in reset
condition (bit 11 set ‘1’)
Note:
12. When “digital zero” is selected as source, the FIFO outputs “zero” on its outgoing data bus, regardless of the input side and
content of the FIFO. No FIFO related exceptions are generated.
Note:
13. When the FIFO leaves the reset state, because the user writes a “normal operation” state into the control register, while
previous state was reset state, the FIFO is kept in reset until the first long-word is written to it. As a result, the “start” of
the normal operation is synchronized with the writing of the first data into the fifo.
Note:
14. When IIS/Sony interface LRCK/SCLK is set in “follow IIS” mode, the bit clock and word clock become exactly identical to bit
and word clock of followed interface. If e.g. LRCK/SCLK for IIS interface 2 is set in “follow IIS1”, the DAC or AD connected
to IIS2 can use bit clock and word clock of IIS1. Bit and word clock for IIS2 can be used as gpio.
Note:
15. Bit 16 extends the Tx FIFO control bit and the bit order becomes 16, 10, 9, 8.
Note:
16. These bits should be programmed zero for normal operation. For interface1 receiver, it is possible to use the special
EF/CFLG insertion mode, by setting bit 18 = 1. This mode is intended to interface with Philips CD decoders (SAA7345 and
successors). When this mode is used, IIS1CONFIG must be programmed to “Sony” mode, 16 bits. The SAA7345 must also
be programmed to “Sony” mode, 16 bits. The CFLG flag coming from SAA7345 must be connected with CFLG input. The
EF flag coming from SAA7345 must be connected with EF input. If all this is done correctly, the device will receive the 16
MSB ‘s of the incoming data in bits [17:2] of the received serial data. Bit [1] of the received data is the EF flag of the
corresponding word, as output by SAA7345. Bit [1] will be set if the MSB or the LSB or both are flagged. Bit [0] of the
received data is the CFLG flag of the corresponding word, as output by SAA7345. These flags can be used for
implementing an electronic shock protection FIFO.
Table 17-7 IIS Configuration Bit Descriptions (Continued)
BIT NAME
BITS
DESCRIPTION