adv601lc Analog Devices, Inc., adv601lc Datasheet - Page 10

• Manufacturer Part Number: adv601lc
• Description: Ultralow Cost Video Codec
• Manufacturer: Analog Devices, Inc.

ADV601LC REGISTER DESCRIPTIONS
Indirect Address Register
Direct (Write) Register Byte Offset 0x00.
This register holds a 16-bit value (index) that selects the indirect register accessible to the host through the indirect data register. All
indirect write registers are 16 bits wide. The address in this register is auto-incremented on each subsequent access of the indirect
data register. This capability enhances I/O performance during modes of operation where the host is calculating Bin Width controls.
[15:0]
[31:16] Reserved (undefined read/write zero)
Indirect Register Data
Direct (Read/Write) Register Byte Offset 0x04
This register holds a 16-bit value read or written from or to the indirect register indexed by the Indirect Address Register.
[15:0]
[31:16] Reserved (undefined read/write zero)
Compressed Data Register
Direct (Read/Write) Register Byte Offset 0x08
This register holds a 32-bit sequence from the compressed video bit stream. This register is buffered by a 512 position, 32-bit FIFO.
For Word (16-bit) accesses, access Word0 (Byte 0 and Byte 1) then Word1 (Byte 2 and Byte 3) for correct auto-increment. For a
description of the data sequence, see the Compressed Data Stream Definition section.
[31:0]
Interrupt Mask / Status Register
Direct (Read/Write) Register Byte Offset 0x0C
This 16-bit register contains interrupt mask and status bits that control the state of the ADV601LC’s HIRQ pin. With the seven
mask bits (IE_LCODE, IE_STATSR, IE_FIFOSTP, IE_FIFOSRQ, IE_FIFOERR, IE_CCIRER, IE_MERR); select the conditions
that are ORed together to determine the output of the HIRQ pin.
Six of the status bits (LCODE, STATSR, FIFOSTP, MERR, FIFOERR, CCIRER) indicate active interrupt conditions and are
sticky bits that stay set until read. Because sticky status bits are cleared when read, and these bits are set on the positive edge of the
condition coming true, they cannot be read or tested for stable level true conditions multiple times.
The FIFOSRQ bit is not sticky. This bit can be polled to monitor for a FIFOSRQ true condition. Note: Enable this monitoring by
using the FIFOSRQ bit and correctly programming DSL and ESL fields within the FIFO control registers.
[0]
[1]
[2]
[3]
ADV601LC
Indirect Address Register, IAR[15:0]. Holds a 16-bit value (index) that selects the indirect register to read or write through
the indirect data register (undefined at reset)
Indirect Register Data, IRD[15:0]. A 16-bit value read or written to the indexed indirect register. Undefined at reset.
Compressed Data Register, CDR[31:0]. 32-bit value containing compressed video stream data. At reset, contents undefined.
CCIR-656 Error in CCIR-656 data stream, CCIRER. This read only status bit indicates the following:
0
1
Statistics Ready, STATSR. This read only status bit indicates the following:
0
1
Last Code Read, LCODE. This read only status bit indicates the last compressed data word for field will be
retrieved from the FIFO on the next read from the host bus.
0
1
FIFO Service Request, FIFOSRQ. This read only status bit indicates the following:
0
1
No CCIR-656 Error condition, reset value
Unrecoverable error in CCIR-656 data stream (missing sync codes)
No Statistics Ready condition, reset value (STATS_R pin LO)
Statistics Ready for BW calculator (STATS_R pin HI)
No Last Code condition, reset value (LCODE pin LO)
Next read retrieves last word for field in FIFO (LCODE pin HI)
No FIFO Service Request condition, reset value (FIFO_SRQ pin LO)
FIFO is nearly full (encode) or nearly empty (decode) (FIFO_SRQ pin HI)
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