Department of Computer Scien

ce and Information Engineering

National Cheng Kung University

HANEL

8051

CONNECTION TO RS232MAX233

‰To save board space, some designers use MAX233 chip from Maxim

¾MAX233 performs the same job as MAX232 but eliminates the need for capacitors¾Notice that MAX233 and MAX232 are not pin compatible

MAX233

8051

Vcc^7

11 15

13 14 12 17 T1in

T1outR1inT2outR2int

R1outT2inR2out

(^541819)
(^23120)
RS232 side
TTL side
6
MAX233
DB-9
112 103
52 43
5
P3.1TxD P3.0RxD
(^16109)