LC6512A(2001) Просмотр технического описания (PDF) - SANYO -> Panasonic

Номер в каталоге

Компоненты Описание

производитель

LC6512A
(Rev.:2001)

Single-Chip 4-Bit Microcomputer for Control-Oriented Applications (Low-Threshold Input, On-Chip FLT Driver)

SANYO -> Panasonic 

LC6512A, LC6513A

Digit drive signal-used key scan

When key-scanning with the FLT digit drive signal in Fig. 3-3 and inputting the return signal to port A, the following must

be observed.

(a) Estimate voltage drop (VON) in the output transistor using the current flowing in an FLT used and the V-I

characteristic of the output port of the LC6512A, 6513A.

(b) Estimate voltage drop (VSW)in the switch circuit.

(c) Check to see that VON + VSW meets the VIH/VIL requirement of the input port in Fig. 3-1.

tDL tDH (External circuit delay time)

Fig. 3-3 Sample key scan application

For the key scan application in Fig. 3-3, make the program considering the delay in the external circuit and the input delay

shown below.

Fig. 3-4

When the IP instruction is used to input the return signal as shown above, the input delay must be considered and two

instructions are placed between the IP instruction and the crossing of input port waveform and VIL(4), VIH(1), respectively.

Some instructions must be placed additionally according to the length of delay (tDL, tDH) in the external circuit after the

digit drive signal is delivered with the execution of the OP instruction (point a and point c).

N: Number of instruction cycles existing between instruction (OP, SPB, RPB) used to output data to output port and

instruction (IP, BP, BNP) used to input data from input port.

(Number of instruction cycles to be programmed according to the length of tDL, tDH)

tDL, tDH: Delay in external circuit from output port to input port.

No.2367–13/24

Share Link: