DS80C320-QNG+ Dallas Semiconductor, DS80C320-QNG+ Datasheet - Page 5

• Manufacturer Part Number: DS80C320-QNG+
• Description: Microcontroller, 8051 Comp., 4 8-Bit I/O Ports, 64K ROM/RAM, 25 MHz, 5 V, PLCC44
• Manufacturer: Dallas Semiconductor

Specifications of DS80C320-QNG+

• Eeprom Memory: 0 Bytes
• Input Output: 32
• Interface: UART
• Memory Type: ROMless
• Number Of Bits: 8
• Package Type: 44-pin PLCC
• Programmable Memory: 0 Bytes
• Ram Size: 256 Bytes
• Speed: 25 MHz
• Timers: 4-8-bit, 3-16-bit
• Voltage, Range: 4.25-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part

PIN DESCRIPTION (continued)
10–17
DIP
21
22
23
24
25
26
27
28
31
—
11, 13–
PLCC
12, 34,
PIN
24
25
26
27
28
29
30
31
19
35
1*
5, 7–13
TQFP
6, 28,
39*
18
19
20
21
22
23
24
25
29
A10 (P2.2)
A11 (P2.3)
A12 (P2.4)
A13 (P2.5)
A14 (P2.6)
A15 (P2.7)
P3.0–P3.7
A8 (P2.0)
A9 (P2.1)
NAME
N.C.
EA
Port 2, Output. Port 2 serves as the MSB for external addressing.
P2.7 is A15 and P2.0 is A8. The device will automatically place the
MSB of an address on P2 for external ROM and RAM access.
Although Port 2 can be accessed like an ordinary I/O port, the value
stored on the Port 2 latch will never be seen on the pins (due to
memory access). Therefore, writing to Port 2 in software is only
useful for the instructions MOVX A, @Ri or MOVX @Ri, A. These
instructions use the Port 2 internal latch to supply the external address
MSB. In this case, the Port 2 latch value will be supplied as the
address information.
Port 3, Input/Output. Port 3 functions as both an 8-bit, bidirectional
I/O port and an alternate functional interface for External Interrupts,
Serial Port 0, Timer 0 & 1 Inputs,
condition of Port 3 is with all bits at logic 1. In this state, a weak
pullup holds the port high. This condition also serves as an input
mode, since any external circuit that writes to the port will overcome
the weak pullup. When software writes a 0 to any port pin, the device
will activate a strong pulldown that remains on until either a 1 is
written or a reset occurs. Writing a 1 after the port has been at 0 will
cause a strong transition driver to turn on, followed by a weaker
sustaining pullup. Once the momentary strong driver turns off, the
port once again becomes both the output high and input state. The
alternate modes of Port 3 are outlined below:
External Access, Active-Low Input. This pin must be connected to
ground for proper operation.
No Connection (Reserved). These pins should not be connected.
They are reserved for use with future devices in this family.
*These pins are reserved for additional ground pins on future products.
DIP
10
11
12
13
14
15
16
17
PLCC
PIN
11
13
14
15
16
17
18
19
5 of 40
TQFP
10
11
12
13
5
7
8
9
PORT
P3.0
P3.1
P3.2
P3.3
P3.4
P3.5
P3.6
P3.7
FUNCTION
ALTERNATE
RXD0
TXD0
RD
INT0
INT1
WR
RD
T0
T1
and
WR
Serial Port 0 Input
Serial Port 0 Output
External Interrupt 0
External Interrupt 1
Timer 0 External Input
Timer 1 External Input
External Data Memory Write
Strobe
External Data Memory Read
Strobe
strobes. The reset
MODE