AT91SAM7X256B-CU Atmel, AT91SAM7X256B-CU Datasheet - Page 588

• Manufacturer Part Number: AT91SAM7X256B-CU
• Description: IC MCU 256KB FLASH 100TFBGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7X256B-CU

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 55MHz
• Connectivity: CAN, Ethernet, I²C, SPI, SSC, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 62
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 64K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TFBGA
• Processor Series: 91S
• Core: ARM7TDMI
• Data Bus Width: 32 bit
• Data Ram Size: 64 KB
• Interface Type: CAN, Ethernet, SPI, I2S, TWI, USART, USB
• Maximum Clock Frequency: 55 MHz
• Number Of Programmable I/os: 62
• Number Of Timers: 3
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Package: 100TFBGA
• Device Core: ARM7TDMI
• Family Name: 91S
• Maximum Speed: 55 MHz
• On-chip Adc: 8-chx10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

37.5.7
Register Name:
Access Type:
This register, when read, provides details of the status of a receive. Once read, individual bits may be cleared by writing 1
to them. It is not possible to set a bit to 1 by writing to the register.
• BNA: Buffer Not Available
An attempt was made to get a new buffer and the pointer indicated that it was owned by the processor. The DMA rereads
the pointer each time a new frame starts until a valid pointer is found. This bit is set at each attempt that fails even if it has
not had a successful pointer read since it has been cleared.
Cleared by writing a one to this bit.
• REC: Frame Received
One or more frames have been received and placed in memory. Cleared by writing a one to this bit.
• OVR: Receive Overrun
The DMA block was unable to store the receive frame to memory, either because the bus was not granted in time or
because a not OK hresp(bus error) was returned. The buffer is recovered if this happens.
Cleared by writing a one to this bit.
588
31
23
15
–
–
–
7
–
AT91SAM7X512/256/128 Preliminary
Receive Status Register
30
22
14
EMAC_RSR
–
–
–
6
–
Read-write
29
21
13
–
–
–
5
–
28
20
12
–
–
–
4
–
27
19
11
–
–
–
3
–
OVR
26
18
10
–
–
–
2
REC
25
17
–
–
9
–
1
6120H–ATARM–17-Feb-09
BNA
24
16
–
–
8
–
0