AT89LP428-20AU Atmel, AT89LP428-20AU Datasheet - Page 124

• Manufacturer Part Number: AT89LP428-20AU
• Description: MCU 8051 4K FLASH SPI 32TQFP
• Manufacturer: Atmel
• Series: 89LPr

Specifications of AT89LP428-20AU

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 30
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2.4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFP, 32-VQFP
• Processor Series: AT89x
• Core: 8051
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: AT89ISP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -
• Lead Free Status / Rohs Status: Details

23.9.3
23.9.4
124
AT89LP428/828
ISP Start Sequence
ISP Exit Sequence
Execute this sequence to exit CPU execution mode and enter ISP mode when the device has
passed Power-on Reset and is already operational.
Figure 23-7. In-System Programming (ISP) Start Sequence
Execute this sequence to exit ISP mode and resume CPU execution mode.
Figure 23-8. In-System Programming (ISP) Exit Sequence
Note:
1. Drive RST low.
2. Drive SS high.
3. Wait t
4. Start programming session.
1. Drive SCK low.
1. Wait at least t
2. Tristate MOSI.
3. Wait at least t
4. Tristate SCK.
5. Wait t
XTAL1
The waveforms on this page are not to scale.
MISO
MOSI
RST
SCK
V
SS
RLZ
RHZ
CC
XTAL1
MISO
MOSI
SCK
RST
V
SS
+ t
CC
and tristate SS.
STL
SSD
SSZ
.
and bring RST high.
and drive SS high.
t
SSD
t
SSZ
t
t
RLZ
RHZ
HIGH Z
HIGH Z
t
STL
HIGH Z
HIGH Z
t
ZSS
t
SSE
3654A–MICRO–8/09