EM78P257
OTP ROM
Table 1 Pin Description- EM78P257AP/AM
Symbol
VDD
OSCI
Pin No.
14
Type
Function
-
I
Power supply.
16
* XTAL type: Crystal input terminal or external clock input pin.
* RC type: RC oscillator input pin.
OSCO
15
I/O * XTAL type: output terminal for crystal oscillator or external clock
input pin.
* RC type: clock output with a duration of one instruction cycle.
* External clock signal input.
P70~P71
P60~P67
4,15
I/O * General purpose I/O pin. (P71 is input pin only)
* Default value after a power on reset.
I/O * General purpose I/O pin.
6~13
* Open_drain
* Default value after a power on reset.
P50~P55
1~3
I/O * General purpose I/O pin.
16~18
* Pull_high/pull_down.
* Wake up from sleep mode when the status of the pin changes.
* Default value after a power on reset.
IR OUT
/INT
13
6
16,17
3,2
7,8
12,11
18,1
9,10
3
O
I
I
I
I
* IR mode output pin, capable of sinking 20mA
* External interrupt pin triggered by falling edge.
* “ -“ -> the input pin of Vin- of a comparator.
* “ +” -> the input pin of Vin+ of a comparator.
* Pin CO1~4 are the outputs of the comparators.
CIN1-,CIN1+
CIN2-,CIN2+
CIN3-,CIN3+
CIN4-,CIN4+
CO1,CO2
CO3,CO4
TCC
I
O
O
I
* External Counter input.
TCC1,TCC2,
TCC3,TCC4
/RESET
,7,12
18,17
4
I
* If set as /RESET and remains at logic low, the device will be reset.
* Voltage on /RESET/Vpp must not exceed Vdd during the normal
mode.
* Pull_high is on if defined as /RESET.
VSS
5
-
Ground.
Table 2 Pin Description- EM78P257AKM
Symbol Pin No. Type
VDD
Function
15,16
18
-
I
Power supply.
OSCI
* XTAL type: Crystal input terminal or external clock input pin.
* RC type: RC oscillator input pin.
OSCO
17
I/O * XTAL type: output terminal for crystal oscillator or external clock
input pin.
* RC type: clock output with a duration of one instruction cycle.
* External clock signal input.
P70,P71
P60~P67
17,4
I/O * General purpose I/O pin. (P71 is input pin only)
* Default value after a power on reset.
I/O * General purpose I/O pin.
7~14
* Open_drain.
* Default value after a power on reset.
P50~P55
1~3
I/O * General purpose I/O pin.
18~20
* Pull_high/pull_down.
This specification is subject to change without prior notice.
7
07.27.2004 (V1.4)
ELAN [ ELAN MICROELECTRONICS CORP ]
