AT91SAM7X128 Atmel, AT91SAM7X128 Datasheet - Page 208
![no-image](/images/manufacturer_photos/0/0/78/atmel_sml.jpg)
AT91SAM7X128
Manufacturer Part Number
AT91SAM7X128
Description
MCU 32-Bit 91S ARM7TDMI RISC 128KB Flash 1.8V/3.3V 100-Pin LQFP
Manufacturer
Atmel
Datasheet
1.AT91SAM7X512-AU-999.pdf
(687 pages)
Specifications of AT91SAM7X128
Package
100LQFP
Device Core
ARM7TDMI
Family Name
91S
Maximum Speed
55 MHz
Ram Size
32 KB
Program Memory Size
128 KB
Operating Supply Voltage
1.8|3.3 V
Data Bus Width
32 Bit
Program Memory Type
Flash
Number Of Programmable I/os
62
Interface Type
CAN/Ethernet/SPI/I2S/TWI/USART/USB
On-chip Adc
8-chx10-bit
Operating Temperature
-40 to 85 °C
Number Of Timers
3
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
AT91SAM7X128-AU
Manufacturer:
ATMEL
Quantity:
1 045
Part Number:
AT91SAM7X128-AU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Part Number:
AT91SAM7X128-CU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
AT91SAM7X128B-AU
Manufacturer:
Atmel
Quantity:
1 929
Part Number:
AT91SAM7X128B-AU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
- Current page: 208 of 687
- Download datasheet (11Mb)
26.4.2
26.4.2.1
26.4.2.2
208
AT91SAM7X512/256/128 Preliminary
Receiver
Receiver Reset, Enable and Disable
Start Detection and Data Sampling
Figure 26-3. Baud Rate Generator
After device reset, the Debug Unit receiver is disabled and must be enabled before being used.
The receiver can be enabled by writing the control register DBGU_CR with the bit RXEN at 1. At
this command, the receiver starts looking for a start bit.
The programmer can disable the receiver by writing DBGU_CR with the bit RXDIS at 1. If the
receiver is waiting for a start bit, it is immediately stopped. However, if the receiver has already
detected a start bit and is receiving the data, it waits for the stop bit before actually stopping its
operation.
The programmer can also put the receiver in its reset state by writing DBGU_CR with the bit
RSTRX at 1. In doing so, the receiver immediately stops its current operations and is disabled,
whatever its current state. If RSTRX is applied when data is being processed, this data is lost.
The Debug Unit only supports asynchronous operations, and this affects only its receiver. The
Debug Unit receiver detects the start of a received character by sampling the DRXD signal until
it detects a valid start bit. A low level (space) on DRXD is interpreted as a valid start bit if it is
detected for more than 7 cycles of the sampling clock, which is 16 times the baud rate. Hence, a
space that is longer than 7/16 of the bit period is detected as a valid start bit. A space which is
7/16 of a bit period or shorter is ignored and the receiver continues to wait for a valid start bit.
When a valid start bit has been detected, the receiver samples the DRXD at the theoretical mid-
point of each bit. It is assumed that each bit lasts 16 cycles of the sampling clock (1-bit period)
so the bit sampling point is eight cycles (0.5-bit period) after the start of the bit. The first sampling
point is therefore 24 cycles (1.5-bit periods) after the falling edge of the start bit was detected.
Each subsequent bit is sampled 16 cycles (1-bit period) after the previous one.
MCK
16-bit Counter
CD
OUT
0
CD
>1
1
0
Divide
by 16
Baud Rate
Receiver
Sampling Clock
6120H–ATARM–17-Feb-09
Clock
Related parts for AT91SAM7X128
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![AT91SAM9R64-CU](/photos/12/13/121356/144-lfbga_tmb.jpg)
Part Number:
Description:
MCU ARM9 64K SRAM 144-LFBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM7A3-AU](/photos/6/76/67646/313-100-lqfp_tmb.jpg)
Part Number:
Description:
IC ARM7 MCU FLASH 256K 100LQFP
Manufacturer:
Atmel
Datasheet:
![AT91SAM9G20B-CU](/photos/12/13/121366/217-lfbga_tmb.jpg)
Part Number:
Description:
IC ARM9 MPU 217-LFBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM9261B-CU](/photos/12/13/121366/217-lfbga_tmb.jpg)
Part Number:
Description:
MCU ARM9 ULTRA LOW PWR 217-LFBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM9G45-CU](/photos/12/13/121367/324-tfbga-pkg_tmb.jpg)
Part Number:
Description:
MCU ARM9 324-TFBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM9G10-CU](/photos/12/13/121366/217-lfbga_tmb.jpg)
Part Number:
Description:
IC MCU ARM9 SAMPLING 217CBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM9260B-CU](/photos/12/13/121366/217-lfbga_tmb.jpg)
Part Number:
Description:
IC ARM9 MCU 217-LFBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM9260B-QU](/photos/6/73/67311/313-208-pqfp_tmb.jpg)
Part Number:
Description:
IC ARM9 MCU 208-PQFP
Manufacturer:
Atmel
Datasheet:
![AT91SAM7X512-AU](/photos/6/76/67646/313-100-lqfp_tmb.jpg)
Part Number:
Description:
MCU ARM 512K HS FLASH 100-LQFP
Manufacturer:
Atmel
Datasheet:
![AT91SAM7X512-CU](/photos/6/89/68968/313-100-cbga_tmb.jpg)
Part Number:
Description:
MCU ARM 512K HS FLASH 100-TFBGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM9263B-CU](/photos/12/13/121367/324-tfbga-pkg_tmb.jpg)
Part Number:
Description:
IC ARM9 MCU 200 MHZ 324-TFBGA
Manufacturer:
Atmel
Datasheet:
![AT91RM9200-CJ-002](/photos/12/32/123245/256-bga_tmb.jpg)
Part Number:
Description:
IC ARM MCU 16BIT 128K 256BGA
Manufacturer:
Atmel
Datasheet:
![AT91SAM7S128-AU-001](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
IC ARM7 MCU 32BIT 128K 64LQFP
Manufacturer:
Atmel
Datasheet:
![AT91SAM7SE256-AU](/photos/6/71/67112/128-lqfp_tmb.jpg)
Part Number:
Description:
IC ARM7 MCU FLASH 256K 128-LQFP
Manufacturer:
Atmel
Datasheet:
![AT91SAM7SE512-AU](/photos/6/71/67112/128-lqfp_tmb.jpg)
Part Number:
Description:
IC ARM7 MCU FLASH 512K 128-LQFP
Manufacturer:
Atmel
Datasheet: