DS89C420-MNL Maxim Integrated Products, DS89C420-MNL Datasheet - Page 10

• Manufacturer Part Number: DS89C420-MNL
• Description: IC MCU ULTRA 33MHZ HP 40-DIP
• Manufacturer: Maxim Integrated Products
• Series: 89Cr

Specifications of DS89C420-MNL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 33MHz
• Connectivity: EBI/EMI, SIO, UART/USART
• Peripherals: Power-Fail Reset, WDT
• Number Of I /o: 32
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

Figure 4. Serial Port Timing
SERIAL PORT (SYNCHRONOUS MODE)
SM2 = 1
SERIAL PORT (SYNCHRONOUS MODE)
SM2 = 0
WRITE TO SCON
TO CLEAR RI
WRITE TO SBUF
RXD DATA OUT
TXD CLOCK
RXD DATA IN
TXD CLOCK
WRITE TO SBUF
RXD DATA OUT
WRITE TO SCON
TO CLEAR RI
TXD CLOCK
RXD DATA IN
TXD CLOCK
PSEN
TXD CLOCK
ALE
TI
R1
PSEN
ALE
TI
R1
TDX CLOCK = XTAL FREQ/4
TDX CLOCK = XTAL FREQ/12
t
XHDV
t
QVXH
D0
t
D0
XLXL
t
XHQX
DI
DI
D2
D0
D2
D0
10 of 47
D3
t
XHDX
D3
1/(XTAL FREQ/12)
D4
D4
DI
D5
DI
D5
D6
D6
D6
D6
D7
D7
D7
D7
TRANSMIT
RECEIVE