AT89LP6440-20AU Atmel, AT89LP6440-20AU Datasheet - Page 160

• Manufacturer Part Number: AT89LP6440-20AU
• Description: MCU 8051 64K FLASH ISP 44TQFP
• Manufacturer: Atmel
• Series: 89LPr

Specifications of AT89LP6440-20AU

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 38
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 8K x 8
• Ram Size: 4.25K x 8
• Voltage - Supply (vcc/vdd): 2.4 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Package: 44TQFP
• Device Core: 8051
• Family Name: 89LP
• Maximum Speed: 20 MHz
• Operating Supply Voltage: 2.5|3.3 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 38
• Interface Type: 2-Wire/SPI
• On-chip Dac: 8-chx10-bit
• Number Of Timers: 3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

25.3
160
Command Format
AT89LP6440 - Preliminary
Figure 25-3. AT89LP6440 Memory Organization
Programming commands consist of an opcode byte, two address bytes, and zero or more data
bytes. In addition, all command packets must start with a two-byte preamble of AAH and 55H.
The preamble increases the noise immunity of the programming interface by making it more dif-
ficult to issue unintentional commands.
a command sequence.
A sample command packet is shown in
frame. SS must be brought low before the first byte in a command is sent and brought back high
after the final byte in the command has been sent. The command is not complete until SS
returns high. Command bytes are issued serially on MOSI. Data output bytes are received seri-
ally on MISO. Packets of variable length are supported by returning SS high when the final
required byte has been transmitted. In some cases command bytes have a don’t care value.
Don’t care bytes in the middle of a packet must be transmitted. Don’t care bytes at the end of a
packet may be ignored.
Page oriented instructions always include a full 16-bit address. The higher order bits select the
page and the lower order bits select the byte within that page. The AT89LP6440 allocates 6 bits
for byte address, 1 bit for low/high half page selection and 9 bits for page address. The half page
to be accessed is always fixed by the page address and half select as transmitted. The byte
address specifies the starting address for the first data byte. After each data byte has been
transmitted, the byte address is incremented to point to the next data byte. This allows a page
command to linearly sweep the bytes within a page. If the byte address is incremented past the
last byte in the half page, the byte address will roll over to the first byte in the same half page.
While loading bytes into the page buffer, overwriting previously loaded bytes will result in data
corruption.
Atmel Signature Array
User Signature Array
Code Memory
Data Memory
User Fuse Row
Figure 25-4 on page 161
Figure 25-5 on page
00
Page 511 Low
Page 510 Low
Page 63 Low
Page 0 Low
Page 1 Low
Page 0 Low
Page 0 Low
Page 0 Low
Page 1 Low
Page 0 Low
00
Page Buffer
3F
40
161. The SS pin defines the packet
Page 511 High
Page 510 High
Page 63 High
Page 1 High
Page 0 High
Page 0 High
Page 0 High
Page 1 High
Page 1 High
3F
shows a simplified flow chart of
7F
3FFF
1000
FFFF
0000
3706A–MICRO–9/09