1

00:00:00,433 --> 00:00:04,200

Hello everyone, today we will learn about the standby conditions

2

00:00:04,200 --> 00:00:06,066

in the standard timing of Loongson's LS7A1000 chipset

3

00:00:11,866 --> 00:00:15,366

First, let's take a look at this timing diagram

4

00:00:16,400 --> 00:00:25,000

In this timing diagram, the condition in the previous part is the standby condition

5

00:00:27,466 --> 00:00:37,666

The first one is called RTC_3V, which is the power supply of the RTC circuit, normally 3.3V,

6

00:00:39,233 --> 00:00:44,400

usually provided by a button battery, or by the standby power supply in the motherboard

7

00:00:46,200 --> 00:00:52,166

The second condition RTC_RTCRSTn, this is the reset signal of the RTC circuit, 3.3V

8

00:00:55,700 --> 00:01:00,933

The third condition is ACPI_3V3, which is the main standby power supply 3.3V

9

00:01:02,833 --> 00:01:08,166

VDD_RSM which is also the main standby power supply 1.1 volts

10

00:01:08,700 --> 00:01:16,100

Next, RTC_RSMRSTn is the good signal of the main standby power supply, 3.3V

11

00:01:19,000 --> 00:01:26,133

The name of this signal is followed by the letter "n", indicating that this signal is active low

12

00:01:27,233 --> 00:01:34,200

For example, ACPI_BATLOWn, this signal is a low battery indicator signal

13

00:01:34,200 --> 00:01:45,833

It includes battery power supply and power supply, the accurate meaning of this signal should be PWRLOWn

14

00:01:46,366 --> 00:01:53,566

Whether it is battery-powered or power-powered, when this signal is low,

15

00:01:53,566 --> 00:01:58,066

it means that the battery is low, normally 3.3V

16

00:01:58,366 --> 00:02:02,400

The signal name is followed by "n" to indicate active low

17

00:02:02,633 --> 00:02:08,133

ACPI_PWRBTNn is the power switch signal

18

00:02:10,866 --> 00:02:14,300

During normal standby, it is 3.3V high level

19

00:02:14,900 --> 00:02:19,666

When we press the switch, it will be pulled down to low level,

20

00:02:20,000 --> 00:02:23,333

and it will return to high level after releasing the switch

21

00:02:26,100 --> 00:02:29,366

We call this a "high-low-high" transition

22

00:02:31,000 --> 00:02:37,500

Next, VSB_GATEn is the main power and Standby power switching signal

23

00:02:40,100 --> 00:02:47,666

Well, these are the standby conditions for the Loongson LS7A1000 chipset