AT89C5132
Bit
Bit Number Mnemonic Description
Reserved
The value read from these bits is always 0. Do not set these bits.
7-6
5
–
Audio Sample Request Flag Mask Bit
Set to prevent the SREQ flag from generating an audio interrupt.
Clear to allow the SREQ flag to generate an audio interrupt.
MSREQ
Audio Sample Under-run Flag Mask Bit
Set to prevent the UDRN flag from generating an audio interrupt.
Clear to allow the UDRN flag to generate an audio interrupt.
4
MUDRN
Reserved
3
–
The value read from this bit is always 0. Do not set this bit.
Audio Duplication Factor
Refer to Table 50 for bits description.
2-1
DUP1:0
Audio Interface Enable Bit
Set to enable the audio interface.
Clear to disable the audio interface.
0
AUDEN
Reset Value = 1011 0010b
Table 53. AUDSTA Register
AUDSTA (S:9Ch Read Only) – Audio Interface Status Register
7
6
5
4
-
3
-
2
-
1
-
0
-
SREQ
UDRN
AUBUSY
Bit
Bit Number Mnemonic Description
Audio Sample Request Flag
Set in C51 audio source mode when the audio interface request samples (buffer half
empty). This bit generates an interrupt if not masked and if enabled in IEN0.
Cleared by hardware when samples are loaded in AUDDAT.
7
6
SREQ
UDRN
Audio Sample Under-run Flag
Set in C51 audio source mode when the audio interface runs out of samples (buffer
empty). This bit generates an interrupt if not masked and if enabled in IEN0.
Cleared by hardware when samples are loaded in AUDDAT.
Audio Interface Busy Bit
Set in C51 audio source mode when the audio interface cannot accept more sample
(buffer full).
5
AUBUSY
Cleared by hardware when buffer is no more full.
Reserved
The value read from these bits is always 0. Do not set these bits.
4-0
-
Reset Value = 1100 0000b
Table 54. AUDDAT Register
AUDDAT (S:9Dh) – Audio Interface Data Register
7
6
5
4
3
2
1
0
AUD7
AUD6
AUD5
AUD4
AUD3
AUD2
AUD1
AUD0
65
4173E–USB–09/07
ATMEL [ ATMEL ]
