AT89C5132 Atmel Corporation, AT89C5132 Datasheet - Page 63

• Manufacturer Part Number: AT89C5132
• Manufacturer: Atmel Corporation

Specifications of AT89C5132

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 20 MHz
• Cpu: 8051-12C
• Max I/o Pins: 44
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Uart: 1
• Adc Channels: 2
• Adc Resolution (bits): 10
• Adc Speed (ksps): 22.7
• Sram (kbytes): 2.25
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 3.6
• Timers: 2
• Isp: UART/USB
• Watchdog: Yes

14.5
14.6
4173E–USB–09/07
Interrupt Request
Voice or Sound Playing
Table 50. Sample Duplication Factor
The audio interrupt request can be generated by two sources when in C51 audio mode: a sam-
ple request when SREQ flag in AUDSTA register is set to logic 1, and an under-run condition
when UDRN flag in AUDSTA register is set to logic 1. Both sources can be enabled separately
by masking one of them using the MSREQ and MUDRN bits in AUDCON1 register. A global
enable of the audio interface is provided by setting the EAUD bit in IEN0 register.
The interrupt is requested each time one of the two sources is set to one. The source flags are
cleared by writing some data in the audio buffer through AUDDAT, but the global audio interrupt
flag is cleared by hardware when the interrupt service routine is executed.
Figure 14-5. Audio Interface Interrupt System
In voice or sound playing mode, the operations required are to configure the PLL and the audio
interface according to the DAC selected. The audio clock is programmed to generate the 256·Fs
or 384·Fs. The data flow sent by the C51 is then regulated by interrupt and data is loaded 4
Bytes by 4 Bytes. Figure 14-6 shows the configuration flow of the audio interface when in voice
or sound mode.
DUP1
0
0
1
1
AUDSTA.6
AUDSTA.7
UDRN
SREQ
DUP0
0
1
0
1
Factor
No sample duplication, DAC rate = 8 kHz (C51 rate).
One sample duplication, DAC rate = 16 kHz (2 x C51 rate).
Two samples duplication, DAC rate = 32 kHz (4 x C51 rate).
Three samples duplication, DAC rate = 48 kHz (6 x C51 rate).
AUDCON1.4
AUDCON1.5
MUDRN
MSREQ
EAUD
IEN0.6
AT89C5132
Audio
Interrupt
Request
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