AT89C51SND1C_14 Datasheet, PDF (1/4 Pages) ATMEL Corporation – Programmable Audio Output for Interfacing with Common Audio DAC

Active AT89C51SND1C Errata List
• SPI Controller – Bad Transfer in Slave Mode with CPHA = 0
• C51 Core – Bad Exit of Power-down in X2 Mode
• MP3 Decoder – Bad Cut Frequency of Bass, Medium, Treble Control
• MP3 Decoder – Bass Boost Effect
• MP3 Decoder – Sampling Frequency Report in MP3 Status Register
• MP3 Decoder – Extra Power Consumption after Reset
AT89C51SND1C Errata History
Lot Number
A01539 and below
A01639 and above
Errata List
1, 2, 3, 4
1, 2, 4, 5, 6, 7
AT89C51SND1C Errata Description
1. SPI Controller – Bad Transfer in Slave Mode with CPHA = 0
SPI controller used in slave mode with CPHA = 0 leads to erratic data reception
and transmission.
Workaround
Use slave mode only with CPHA = 1.
2. C51 Core – Bad Exit of Power-down in X2 Mode
When exiting Power-down mode by interrupt while CPU is in X2 mode, it leads to
bad execution of first instruction executed when CPU restarts.
Workaround
Put the CPU in X1 mode just before entering power-down mode.
3. MP3 Decoder – Underrun When Playing High Bit-Rate Frames
When playing frames with the following frequencies sampling and bit rates, audio
DAC runs out of data leading to noise and wow.
– 44.1 kHz - 320 Kbs
– 32 kHz - 256 Kbs, 320 Kbs
Workaround
Implemented in latest firmware packages.
4. MP3 Decoder – Bad Cut Frequency of Bass, Medium, Treble Control
The cut frequency of bass control is 300 Hz instead of 750 Hz and cut frequency
of treble control is 2 kHz instead of 3.3 kHz.
Workaround
No workaround available.
5. MP3 Decoder – Bass Boost Effect
Enabling the built-in bass boost effect with some MP3 song leads to sound
distorsion.
Workaround
Use the equalizer bass band control instead of bass boost control.
MP3
Microcontrollers
AT89C51SND1C
Errata Sheet
4197C–MP3–02/06