SC73P1601

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

REV:1.4

2009.08.03

Http: www.silan.com.cn

Page 8 of 22

14. PORT

SC73P1601 has 4 groups of I/O ports, totally 20 pins. Each group can operate in both input and output mode

(except P50 and P53, P50 is only input port, P53 is only output port). Details are as follows:

P0 port: P00-P03, 4-bit input/output port. The PR determines the port operation mode. In input mode, it has an

internal pull-down resistor and can be used for keyboard scan input. When the input level is high, it

can release the HOLD mode. In output mode, it can be used for keyboard scan output.

P1 port: P10-P13, same as P0 port;

P2 port: P20-P23, same as P0 port;

P5 port: P50-P53

P50: only as input pin with pull-down resistor used for keyboard scan input. When input high level, the

HOLD state is unlocked.

P51: the configuration same as P00;

P52: the configuration same as P00;

P53: large current output port, this pin is used to output infrared remote signal. If P53 is set to 1, this

pin outputs modulated signal with carrier or high level signal. If it is set to 0, it outputs low level

voltage.

15. Timer/counter

SC73P1601 has two internal timers:

One is a 17-bit timer. The clock source of the timer is main frequency (fmain) of the circuit. There are timing

steps from 10 (which generates pulses with frequency fmain/210) to 15 (fmain/215). The timer can output pulse

frequency ranging from fmain/210 to fmain/215, and can be used for timer after releasing the HOLD mode. It can

also be used as a WDT. After the HOLD mode released and the timer reset instruction TMRST executed, the

timer value is cleared.

The other timer is a carrier generator. Setting different length of high and low level time span respectively

through programming, it generates various different duty and frequency carriers.

16. TR

Timer register, it selects the status of the timer mode, use the instruction LD TM, A to write the data.

SC73P1601 uses the instruction LD A, TM or LD @LR, TM to read the status of timer; TM to read the timing

value. For example:

3

IBNS

TR timer register

TIBS

2

1

0

17. IBNS

The control bit of the read timer. When the value is 0, it reads TM3 (IT3), and IT2~IT0 become 0. When the value

is 1, it reads 4-bit data TM3~TM0(IT3~IT0).

TM3: 2

TM2: 2

TM1: 2

TM0: 2