89C5121-SK1 Atmel, 89C5121-SK1 Datasheet - Page 9

• Manufacturer Part Number: 89C5121-SK1
• Description: KIT SMART CARD FOR AT89C5121
• Manufacturer: Atmel
• Type: Smart Cardr

Specifications of 89C5121-SK1

• Contents: Board
• For Use With/related Products: AT89C5121
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: T89C5121-SK1; T89C5121-SK1

Table 1. Ports Description (Continued)
4164G–SCR–07/06
ONLY FOR PLCC52 version
P0[7:0]
P2[7:0]
PSEN
Port
P3.6
P3.7
ALE
EA
Signal
AD[7:0]
Name
A[15:8]
PSEN
WR
RD
EA
Alternate
Internal
Supply
Power
DV
DV
V
V
V
V
V
CC
CC
CC
CC
CC
CC
CC
ESD
Type
I/O
I/O
I/O
O
O
O
O
I
I
Description
Input/Output function Port 0
P0 is an 8-bit open-drain bi-directional I/O port. Port 0 pins that
have 1s written to them float and can be used as high impedance
inputs. To avoid any parasitic current consumption, Floating P0
inputs must be pulled to V
Address/Data low
Mutiplexed Address/Data LSB for external access
Input/Output function Port 2
P2 is an 8-bit open-drain bi-directional I/O port with internal pull-ups
Address high
Address Bus MSB for external access
Write signal
Write signal asserted during external data memory write operation
Read signal
Read signal asserted during external data memory read operation
Address latch enable output
The falling edge of ALE strobes the address into external latch
Program strobe enable
External access enable
This pin must be held low to force the device to fetch code from
external program memory starting at address 0000h. It is latched
during reset and cannot be dynamically changed during operation.
CC
or V
SS
.
A/T8xC5121
9