구차니의 잡동사니 모음

Description

 Shifts the bits in the first operand (destination operand) to the left or right by the number of bits specified in the second operand (count operand). Bits shifted beyond the destination operand boundary are first shifted into the CF flag, then discarded. At the end of the shift operation, the CF flag contains the last bit shifted out of the destination operand. The destination operand can be a register or a memory location. The count operand can be an immediate value or the CL register. The count is masked to 5 bits (or 6 bits if in 64-bit mode and REX.W is used). The count range is limited to 0 to 31 (or 63 if 64-bit mode and REX.W is used). A special opcode encoding is provided for a count of 1. The shift arithmetic left (SAL) and shift logical left (SHL) instructions perform the same operation; they shift the bits in the destination operand to the left (toward more significant bit locations). For each shift count, the most significant bit of the destination operand is shifted into the CF flag, and the least significant bit is cleared (see Figure 7-7 in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 1).

 The shift arithmetic right (SAR) and shift logical right (SHR) instructions shift the bits of the destination operand to the right (toward less significant bit locations). For each shift count, the least significant bit of the destination operand is shifted into the CF flag, and the most significant bit is either set or cleared depending on the instruction type. The SHR instruction clears the most significant bit (see Figure 7-8 in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 1); the SAR instruction sets or clears the most significant bit to correspond to the sign (most significant bit) of the original value in the destination operand. In effect, the SAR instruction fills the empty bit position’s shifted value with the sign of the unshifted value (see Figure 7-9 in the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 1). 

case 4:

packet[4] = (val >> 24) & 0xFF;

0115687B  mov         ebx,ecx  

0115687D  sar         ebx,18h  

01156880  mov         byte ptr [edi+4],bl  

packet[5] = (val >> 16) & 0xFF;

01156883  mov         ebx,ecx  

01156885  sar         ebx,10h  

01156888  mov         byte ptr [edi+5],bl  

packet[6] = (val >> 8) & 0xFF;

0115688B  mov         ebx,ecx  

0115688D  sar         ebx,8  

01156890  mov         byte ptr [edi+6],bl  

packet[7] = (val) & 0xFF;

01156893  mov         byte ptr [edi+7],cl  

break;

01156896  jmp         $LN11+54h (11568A8h)  

break; 

Pins 1 through 9 carry the three TMDS data channels (Transition Minimized Differential Signaling – the technology that allows DVI and HDMI to send high-speed digital data), three pins per channel. TMDS data includes both video and audio information, and each channel has three separate lines for + values, - values, and a ground or data shield.

Pins 10 through 12 carry data for the TMDS clock channel, which helps keep the signals in synchronization. As with the TMDS data channels, there are separate lines for + values, - values, and a data shield.

Pin 13 is carries the CEC (Consumer Electronics Control) channel, used for sending command and control data between connected devices.

Pin 14 is reserved for future use.

Pins 15 and 16 are dedicated to the DDC (Display Data Channel), used for communicating EDID (Extended Display Identification Channel) information between devices.

Pin 17 is a data shield for the CEC and DDC channels.

Pin 18 carries a low-voltage (+5V) power supply.

Pin 19 is the Hot Plug Detect, dedicated to monitoring power up/down and plug/unplug events. 

Basics

 HDMI leverages on the successful transition minimized differential signaling (TMDS) technology. The differential signals are +3.3 Volts, terminated in 50 Ω with nominal amplitude transitions of 500 mV (+2.8 V to +3.3 V). The voltage swing can vary from 150 mV to 800 mV. The signals have rise times of the order of 100 ps 

6.2.2 Video Control Signals : HSYNC, VSYNC

During the Data Island period, HDMI carries HSYNC and VSYNC signals using encoded bits on Channel 0. During Video Data periods, HDMI does not carry HSYNC and VSYNC and the Sink should assume that these signals remain constant. During Control periods, HDMI carries HSYNC and VSYNC signals through the use of four different control characters on TMDS Channel 0. 

A VGA video signal contains 5 active signals:

• horizontal sync: digital signal, used for synchronisation of the video

• vertical sync: digital signal, used for synchronisation of the video

• red (R): analog signal (0-0.7 v), used to control the color

• green (G): analog signal (0-0.7 v), used to control the color

• blue (B): analog signal (0-0.7 v), used to control the color