[media] cx88.rst: add contents of hauppauge-wintv-cx88-ir.txt

Import the contents of hauppauge-wintv-cx88-ir.txt, after
converted to ReST into cx88.rst file.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Mauro Carvalho Chehab 2016-07-18 14:18:10 -03:00
parent 2b8de4eabc
commit f0d17227d7
3 changed files with 62 additions and 108 deletions

View file

@ -98,3 +98,65 @@ MO_OUTPUT_FORMAT (0x310164)
0x47 is the sync byte for MPEG-2 transport stream packets.
Datasheet incorrectly states to use 47 decimal. 188 is the length.
All DVB compliant frontends output packets with this start code.
Hauppauge WinTV cx88 IR information
-----------------------------------
The controls for the mux are GPIO [0,1] for source, and GPIO 2 for muting.
====== ======== =================================================
GPIO0 GPIO1
====== ======== =================================================
0 0 TV Audio
1 0 FM radio
0 1 Line-In
1 1 Mono tuner bypass or CD passthru (tuner specific)
====== ======== =================================================
GPIO 16(I believe) is tied to the IR port (if present).
From the data sheet:
- Register 24'h20004 PCI Interrupt Status
- bit [18] IR_SMP_INT Set when 32 input samples have been collected over
- gpio[16] pin into GP_SAMPLE register.
What's missing from the data sheet:
- Setup 4KHz sampling rate (roughly 2x oversampled; good enough for our RC5
compat remote)
- set register 0x35C050 to 0xa80a80
- enable sampling
- set register 0x35C054 to 0x5
- enable the IRQ bit 18 in the interrupt mask register (and
provide for a handler)
GP_SAMPLE register is at 0x35C058
Bits are then right shifted into the GP_SAMPLE register at the specified
rate; you get an interrupt when a full DWORD is received.
You need to recover the actual RC5 bits out of the (oversampled) IR sensor
bits. (Hint: look for the 0/1and 1/0 crossings of the RC5 bi-phase data) An
actual raw RC5 code will span 2-3 DWORDS, depending on the actual alignment.
I'm pretty sure when no IR signal is present the receiver is always in a
marking state(1); but stray light, etc can cause intermittent noise values
as well. Remember, this is a free running sample of the IR receiver state
over time, so don't assume any sample starts at any particular place.
Additional info
~~~~~~~~~~~~~~~
This data sheet (google search) seems to have a lovely description of the
RC5 basics:
http://www.atmel.com/dyn/resources/prod_documents/doc2817.pdf
This document has more data:
http://www.nenya.be/beor/electronics/rc5.htm
This document has a how to decode a bi-phase data stream:
http://www.ee.washington.edu/circuit_archive/text/ir_decode.txt
This document has still more info:
http://www.xs4all.nl/~sbp/knowledge/ir/rc5.htm

View file

@ -1,54 +0,0 @@
The controls for the mux are GPIO [0,1] for source, and GPIO 2 for muting.
GPIO0 GPIO1
0 0 TV Audio
1 0 FM radio
0 1 Line-In
1 1 Mono tuner bypass or CD passthru (tuner specific)
GPIO 16(i believe) is tied to the IR port (if present).
------------------------------------------------------------------------------------
>From the data sheet:
Register 24'h20004 PCI Interrupt Status
bit [18] IR_SMP_INT Set when 32 input samples have been collected over
gpio[16] pin into GP_SAMPLE register.
What's missing from the data sheet:
Setup 4KHz sampling rate (roughly 2x oversampled; good enough for our RC5
compat remote)
set register 0x35C050 to 0xa80a80
enable sampling
set register 0x35C054 to 0x5
Of course, enable the IRQ bit 18 in the interrupt mask register .(and
provide for a handler)
GP_SAMPLE register is at 0x35C058
Bits are then right shifted into the GP_SAMPLE register at the specified
rate; you get an interrupt when a full DWORD is received.
You need to recover the actual RC5 bits out of the (oversampled) IR sensor
bits. (Hint: look for the 0/1and 1/0 crossings of the RC5 bi-phase data) An
actual raw RC5 code will span 2-3 DWORDS, depending on the actual alignment.
I'm pretty sure when no IR signal is present the receiver is always in a
marking state(1); but stray light, etc can cause intermittent noise values
as well. Remember, this is a free running sample of the IR receiver state
over time, so don't assume any sample starts at any particular place.
http://www.atmel.com/dyn/resources/prod_documents/doc2817.pdf
This data sheet (google search) seems to have a lovely description of the
RC5 basics
http://www.nenya.be/beor/electronics/rc5.htm and more data
http://www.ee.washington.edu/circuit_archive/text/ir_decode.txt
and even a reference to how to decode a bi-phase data stream.
http://www.xs4all.nl/~sbp/knowledge/ir/rc5.htm
still more info

View file

@ -1,54 +0,0 @@
The controls for the mux are GPIO [0,1] for source, and GPIO 2 for muting.
GPIO0 GPIO1
0 0 TV Audio
1 0 FM radio
0 1 Line-In
1 1 Mono tuner bypass or CD passthru (tuner specific)
GPIO 16(i believe) is tied to the IR port (if present).
------------------------------------------------------------------------------------
>From the data sheet:
Register 24'h20004 PCI Interrupt Status
bit [18] IR_SMP_INT Set when 32 input samples have been collected over
gpio[16] pin into GP_SAMPLE register.
What's missing from the data sheet:
Setup 4KHz sampling rate (roughly 2x oversampled; good enough for our RC5
compat remote)
set register 0x35C050 to 0xa80a80
enable sampling
set register 0x35C054 to 0x5
Of course, enable the IRQ bit 18 in the interrupt mask register .(and
provide for a handler)
GP_SAMPLE register is at 0x35C058
Bits are then right shifted into the GP_SAMPLE register at the specified
rate; you get an interrupt when a full DWORD is received.
You need to recover the actual RC5 bits out of the (oversampled) IR sensor
bits. (Hint: look for the 0/1and 1/0 crossings of the RC5 bi-phase data) An
actual raw RC5 code will span 2-3 DWORDS, depending on the actual alignment.
I'm pretty sure when no IR signal is present the receiver is always in a
marking state(1); but stray light, etc can cause intermittent noise values
as well. Remember, this is a free running sample of the IR receiver state
over time, so don't assume any sample starts at any particular place.
http://www.atmel.com/dyn/resources/prod_documents/doc2817.pdf
This data sheet (google search) seems to have a lovely description of the
RC5 basics
http://www.nenya.be/beor/electronics/rc5.htm and more data
http://www.ee.washington.edu/circuit_archive/text/ir_decode.txt
and even a reference to how to decode a bi-phase data stream.
http://www.xs4all.nl/~sbp/knowledge/ir/rc5.htm
still more info