IS TTC

Introduction

The Target To Connection packet is sent to LFS to request information about a remote connection.

struct IS_TTC // General purpose 8 byte packet (Target To Connection)
{
	byte	Size;		// 8
	byte	Type;		// ISP_TTC
	byte	ReqI;		// 0 unless it is an info request or a reply to an info request
	byte	SubT;		// subtype, from TTC_ enumeration (e.g. TTC_SEL)

	byte	UCID;		// connection's unique id (0 = local)
	byte	B1;			// B1, B2, B3 may be used in various ways depending on SubT
	byte	B2;
	byte	B3;
};

Packet Details

Size

The packet size, always 8 bytes.

Type

The packet type from the ISP_ enumeration, always ISP_TTC.

ReqI

For an info request, this value must bet non-zero, and LFS will include the same ReqI in its reply. Otherwise, it should be zero.

SubT

The packet's subtype, which is a value from the TTC_ enumeration.

• TTC_NONE: Not used.
• TTC_SEL: Send to request an IS_AXM packet for the current layout editor selection.
• TTC_SEL_START: Send to request an IS_AXM packet very time the layout editor selection changes.
• TTC_SEL_STOP: Send to stop receiving [IS_AXM]] packets for every layout editor selection change.

UCID

The connection's unique ID. A value of 0 represents the local connection.

Values

B1, B2, and B3 can contain data depending on the value of SubT. At the time of writing (LFS 0.8B/InSim 10), no sub-type uses those values.