IRIG 106-99 Appendix G, Part 2

IRIG 106-99 APPENDIX G, Continued....

SUBMUX DATA FORMAT FIELD DEFINITIONS

The details of the submux data format are shown in figures G-4a and G-4b and defined in the Submux Data Format Field Definitions Summary. Figure G-5 shows a typical primary channel aggregate data content for fixed and variable rate channel. Submux data format is based on the sequential collection of the individual channel data blocks. Each channel data block is the sequential collection of presented input samples in a fixed period of time. This sequential collection results in a variable length, fixed rate, and channel data blocks. To accommodate fixed rate channels, fill is also defined. The aggregate data stream is composed of a block sync timing channel, followed by sequential channel data blocks, if enabled, followed by fill, if required, at fixed block rate.

The channel data blocks are the sequential collection of input samples bit packed into sequential 16-bit words over the block period of time. The data block is preceded by a three-word header that identifies the source (channel ID) of data, channel type of processing, packing format in the data block, bit count length of the valid data, and the time delay between the first sample and the block period. If data were internally sampled, the sample period is defined with the first sample being coincident with the start of block period. Channel type is used to define specific types of channels that provide timing, annotation, and synchronization functions that may be required by the specific primary channel or may be redundant and not required. Specific implementation of the required channels may provide only the required channels with specific implementation constraints that limit the aggregate rate or the range of any specific field.

The submux format is based on a 16-MHz clock defining all timing. The derived clock is the 16-MHz clock divided in binary steps as defined by 2^BRC that defines all timing and internal sampling. Block period is 20 160 derived clock periods which limits the submux aggregate to 256 Mbps, limits the maximum block rate to 793.65 blocks per second, and in conjunction with a 16-bit bit count field, limits the subchannel maximum data rate to 52 Mbps.

Figure G-4a. Submux data format.

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Figure G-4b. Submux data format.

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Figure G-5. Submux aggregate format.

SUBMUX DATA FORMAT FIELD DEFINITIONS SUMMARY

1. Frame length	Variable or fixed with fill. Minimum is 3-word block sync plus one channel block, maximum is 20 160x16-bit words.
2. Block length	Variable from 3x16-bit words to 4099x16-bit words per channel data block. Specified by CHT>0 and integer of (Bit_ Count+15/16). May be limited by implementation.
3. Block Sync	Defined by Channel ID = 31, 3-word block, 2-word sync. Defines a period of 20 160 derived clocks.
4. General Form	All Channel data blocks contain this information in the 3-word header.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel of any type. CHN ID = 31 reserved for Block Sync.
	(bits 10 to 8)	CHT, Channel Type, from 0 to 7 defines type of processing performed on the data and the format of header word fields.
CHT = 0		Timing channel, block sync or time tag, 3-word only
CHT = 1		Annotation text or block count, variable length
CHT = 2		Digital serial external or internal clock, variable
CHT = 3		Digital parallel external clock, variable
CHT = 4		Analog wide band, variable
CHT = 5		Analog stereo, variable
CHT = 6		TBD (to be defined by future implementation)
CHT = 7		TBD

Variable length

General form with variable data block length

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel of any type.
	(bits 10 to 8)	CHT, Channel Type, from 1 to 7 defines type of processing performed on the data and the format of header word fields.
	(bits 7 to 4)	FMT, Format, defines the number of bits minus one in each sample. Data block sample size (bits) = (FMT+1). Range 0 to 15, binary format.
	(bits 3 to 0)	ST1 to ST4, status bits, define dynamic conditions within this block period such as over range.
HW2	(bits 15 to 0)	Bit_Count defines the number of valid data bits in the data block starting with the most significant bit of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65535, binary format.
HW3	(bit 15)	I/E, Internal / External clock
	(bits 15 to 0)	Depends on CHT field, defines block count, time delay, or sample period.

5. Block Sync

Defines the start of channel data blocks and start of block period that lasts for 20 160 derived clocks.

HW1	(bits 15 to 0)	SYNC 1 = F8C7 hex, defines the first sync word.
HW2	(bits 15 to 0)	SYNC 2 = BF1E hex, defines the second sync word.
HW3	(bits 15 to 13)	BRC, Block Rate Clock, defines the binary divisor for the 16 MHz system clock. Derived CLK = 16 MHz / 2 ^BRC MHz. Block rate = Derived CLK / 20160 Hz. Period = 1 / Derived CLK.
	(bit 12)	FILL, indicates if the primary channel requires fill for constant rate.
	(bits 11 to 4)	TBD
	(bit 3)	AOE, Aggregate Overrun Error if set indicates that the aggregate of the enabled channels exceeds the submux aggregate (data truncated to 20 160 words between sync).
	(bit 2)	PCRE, Primary Channel Rate Error if set indicates that primary channel is unable to maintain the aggregate rate of the submux. Excess blocks are truncated.
	(bits 1 to 0)	ST3, ST4, Status reserved.

6. Time Tag

Defines the time tag channel for time stamping the frame.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 0, Channel Type = 0, Time Tag IRIG Time code processing and 3-word format.
HW	(bits 7 to 0)	DAYS, Most significant 8 bits of Time Code Days field. BCD format.
	(bits 15 to 14)	DAYS, Least significant 2 bits of Time Code Days field. BCD format.
	(bits 13 to 8)	HOURS, Time Code Hours 6 bit field. BCD format.
HW	(bits 7 to 0)	MINUTES, Time Code Minutes 7 bit field. BCD format.
	(bits 15 to 8)	SECONDS, Time Code Seconds 7 bit field. BCD format.
	(bits 7 to 0)	FRACTIONAL SECONDS, Time Code Fractional Seconds 8 bit field. BCD format.

7. Annotation Text

Defines block count and annotation text that pertains to the subchannels at this time.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 1, Channel Type = 1, Block Count and Annotation Text if any.
	(bits 7 to 4)	FMT = 7, Format = 7 , defines 8 bit ASCII character in text.
	(bit 3)	NC, No Characters (Bit_Count = 0) Block count only.
	(bits 2 to 0)	OVR, PE, OE, Overrun Parity and async framing error.
HW	(bits 15 to 0)	Bit_Count defines the number of valid data bits in the data block starting with the MSB of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65 535, binary format.
HW	(bits 15 to 0)	Block_Count sequential block numbering with rollover at maximum. Range 0 to 65 535, binary format.
DW1	(bits 15 to 8)	1st CHARACTER, first text character.
DW	(bits 8 or 0)	Last CHARACTER, LSB is defined by the Bit Count.

8. Digital Serial
External CLK

Defines digital serial data such as PCM externally clocked.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 2, Channel Type = 2, digital serial or data and clock over sampled data.
	(bits 7 to 4)	FMT = 0 Format = 0, defines 1-bit data samples.
	(bit 3)	NSIB, No Samples In Block (Bit_Count=0) header only.
	(bit 2)	OVR, Overrun indicates that input is clocking at faster than specified rate. Data is truncated at specified bit rate (Bit Count per Block).
HW	(bits 15 to 0)	Bit_Count, defines the number of valid data bits in the data block starting with the most significant bit of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65 535, binary format. Limited by set maximum rate.
HW	(bit 15 )	I/E = 0, Internal / External clock flag indicates that external clocking was used with relative phasing to block as specified in next field.
	(bits 14 to 0)	Time Delay provides the measure of time between start of block period and the first external clock in derived clock periods. Range 0 to 20 160, binary format.
DW1	(bit 15)	DS₁, first data sample at the first clock time in the block.
Dw_n	(bit L)	DS_L, last data sample in this block period.

9. Digital Serial
Internal CLK

Defines digital serial data low rate (> 2 samples per block period) internally oversampled.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 2, Channel Type = 2, Digital serial or data and clock over sampled data.
	(bits 7 to 4)	FMT = 0 Format = 0, defines 1-bits data samples.
	(bits 3 to 0)	0, reserved.
HW2	(bits 15 to 0)	Bit_Count defines the number of valid data bits in the data block starting with the most significant bit of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65 535, binary format. Limited by set maximum rate.
HW3	(bit 15)	I/E = 1, Internal Sampling flag indicates that internal sampling was used as specified in next field.
	(bits 14 to 9)	TBD
	(bits 8 to 0)	SAMPLE PERIOD, defines the period of the over-sampling clock that samples data and clock, in derived clock periods. Range 0 to 4 mega samples per second, binary format.
DW1	(bit 15)	DS₁, first data sample at block time.
	(bit 7)	CS₁, first clock sample at block time.
DWn	(bit 8)	DS_L, last data sample in this block period.
	(bit 0)	CS_L, last clock sample in this block period.

10. Digital Parallel
External CLK

Defines digital data including serial externally clocked.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 3, Channel Type = 3, Digital parallel or serial data.
	(bits 7 to 4)	FMT, Format, defines the number of bits minus one in each sample. Data block sample size (bits) = (FMT+1). Range 0 to 15, binary format.
	(bit 3)	NSIB, No Samples In Block (Bit_Count = 0) Header only.
	(bit 2)	OVR, Overrun indicates that input is clocking at faster than specified rate. Data is truncated at specified bit rate (Bit Count per Block).
HW2	(bits 15 to 0)	Bit_Count defines the number of valid data bits in the data block starting with the most significant bit of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65 535, binary format. Limited by set maximum rate.
HW3	(bit 15)	I/E = 0, Internal / External clock flag indicates that external clocking was used with relative phasing to block as specified in next field.
	(bits 14 to 0)	Time delay provides the measure of time between start of block period and the first external clock in derived clock periods. Range 0 to 20 160, binary format.
DW1	(bit 15)	DS₁, MSB of the first data sample at the first clock time in the block.
DW_n	(bit L)	DS_L, LSB of the last data sample in this block period.

11. Analog
Wide Band

Defines analog wide band data using a sampling A/D and internal block synchronous clock.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 4, Channel Type = 4, analog wide band sampled data.
	(bits 7 to 4)	FMT, Format, defines the number of bits minus one in each sample. Data block Sample Size (bits) = (FMT+1). Range 0 to 15, binary format. Limited by the A/D resolution.
	(bit 3)	AOR, Analog over range (A/D 4-msb = F).
	(bits 2 to 0)	ST2 to ST4, reserved status
HW2	(bits 15 to 0)	Bit_Count defines the number of valid data bits in the data block starting with the MSB of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65 535, binary format. Limited by set maximum rate.
HW3	(bit 15)	I/E = 1, Internal Sampling flag indicates that internal sampling was used as specified in next field.
	(bits 14 to 12)	TBD
	(bits 11 to 0)	Sample Period defines the period of the over-sampling clock that samples data and clock, in derived clock periods. Range 0 to 4m samples per second, binary format.
DW1	(bit 15)	DS₁, MSB of the first data sample at the first clock time in the block.
DW_n	(bit L)	DS_L, LSB of the last data sample in this block period.

12. Analog Stereo
"L" & "R"

Defines analog stereo data using a sigma-delta A/D and internal block synchronous clock with tracking Finite Impulse Response (FIR) filter.

HW1	(bits 15 to 11)	CHN ID, Channel ID number, from 0 to 30 binary number represents normal channel.
	(bits 10 to 8)	CHT = 5, Channel Type = 5, Analog stereo voice band data.
	(bits 7 to 4)	FMT, Format defines the number of bits minus one in each sample. Data block sample size (bits) = (FMT+1). Range 0 to 15, binary format. Limited by the A/D resolution.
	(bit 3)	LAOR, left subchannel over range.
	(bit 2)	RAOR, right subchannel over range.
	(bits 1 to 0)	ST2 to ST4, reserved status.
HW2	(bits 15 to 0)	Bit_Count defines the number of valid data bits in the data block starting with the MSB of the first data word DW1. Variable word length of the data block is the Integer of ((Bit_Count + 15)/16). Range 0 to 65 535, binary format. Limited by set maximum rate.
HW3	(bit 15)	I/E = 1, Internal Sampling flag indicates that internal sampling was used as specified in next field.
	(bit 14)	ENL, Enable Left subchannel.
	(bit 13)	ENR, Enable Right subchannel.
	(bit 12)	TBD
	(bits 11 to 0)	Sample period defines the period of the over-sampling clock that samples data and clock, in derived clock periods. Range 3.76 to 40K samples per second, binary format.
DW1	(bit 15)	DS₁, MSB of the first data sample left subchannel if enabled.
	(bit 15- FMT-1)	DS₁, MSB of the first data sample right subchannel if enabled, else second sample.
DWn	(bit L)	DS_L, LSB of the last data sample in this block period.

13. Fill

Defines fill word that can be inserted at the end of all channel data blocks if required by the constant rate primary channel.

Fwx

(bits 15 to 0)

FILL, defined as FFFF hex word.

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