AT89LP6440-20JU Atmel, AT89LP6440-20JU Datasheet - Page 19

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

Specifications of AT89LP6440-20JU

• 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-PLCC
• Processor Series: AT89x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 8 KB
• Interface Type: 2-Wire, SPI
• Maximum Clock Frequency: 24 MHz
• Number Of Programmable I/os: 38
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: AT89ISP
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• On-chip Dac: 10 bit, 8 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.4
3706A–MICRO–9/09
Extended Stack
Figure 3-11. MOVX with One Wait State (WS = 01B)
Figure 3-12. MOVX with Two Wait States (WS = 10B)
Figure 3-13. MOVX with Three Wait States (WS = 11B)
The AT89LP6440 provides an extended stack space for applications requiring additional stack
memory. By default the stack is located in the 256-byte IDATA space of internal data memory.
The IDATA stack is referenced solely by the 8-bit Stack Pointer (SP: 81H). Setting the XSTK bit
in AUXR enables the extended stack. The extended stack resides in the EDATA space for up to
4KB of stack memory. The extended stack is referenced by a 12-bit pointer formed from SP and
the four LSBs of the Extended Stack Pointer (SPX: 9EH) as shown in
between both stacks. Note that the standard IDATA stack will not overflow to the EDATA stack
or vice versa. The stack and extended stack are mutually exclusive and SPX is ignored when
XTSK = 0. An application choosing to switch between stacks by toggling XSTK must maintain
CLK
ALE
CLK
ALE
CLK
ALE
WR
WR
WR
RD
RD
RD
P2
P0
P0
P2
P0
P0
P2
P0
P0
P2 SFR
P0 SFR
P0 SFR
P2 SFR
P0 SFR
P0 SFR
P2 SFR
P0 SFR
P0 SFR
S1
S1
S1
DPL OUT
DPL OUT
DPL OUT
DPL OUT
DPL OUT
DPL OUT
S2
S2
S2
S3
S3
S3
DPH or P2 OUT
DPH or P2 OUT
DATA OUT
FLOAT
W1
W1
W1
DPH or P2 OUT
DATA OUT
FLOAT
DATA OUT
FLOAT
W2
W2
S4
AT89LP6440 - Preliminary
P2 SFR
P0 SFR
P0 SFR
W3
S4
P2 SFR
P0 SFR
P0 SFR
S4
P2 SFR
P0 SFR
P0 SFR
Figure
3-14. SP is shared
19