Memory Mod: Difference between revisions
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==The Idea== |
==The Idea== |
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"[[Full-featured Card|Full-featured]]" DVB cards are equipped with a 2 MByte SDRAM chip. Using the Linux DVB drivers, OSD memory space is limited to approx. 80 KBytes. Therefore, it is not possible to have a full-screen, 256 color OSD when using [[VDR]]. However, the onboard [[AV711x|AV7110/7111 |
"[[Full-featured Card|Full-featured]]" DVB cards are equipped with a 2 MByte SDRAM chip. Using the Linux DVB drivers, OSD memory space is limited to approx. 80 KBytes. Therefore, it is not possible to have a full-screen, 256 color OSD when using [[VDR]]. However, the onboard [[TI AV711x|AV7110/7111]] [[MPEG-2 Decoder]] used by these cards is able to handle/address two 2MByte SDRAM chips. Doubling the amount of addressable memory onboard these cards would effectively resolve the limitation outlined above and, hence, users could gain a full-screen 256 color OSD in VDR. Additionally there would be more space for the video buffers. Given the obvious benefit, why not add the second one? |
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==The Modification== |
==The Modification== |
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[[Image:Memory_Mod_Pic1.jpg|thumb|right|AV7110 and SDRAM chip before modification]] |
[[Image:Memory_Mod_Pic1.jpg|thumb|right|AV7110 and SDRAM chip before modification]] |
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The chip select for the second SDRAM chip is not available on the pcb itself, so the AV7110 processor and the memory chip have to be modified. |
The chip select for the second SDRAM chip is not available on the pcb itself, so the [[TI AV711x|AV7110]] processor and the memory chip have to be modified. |
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In the image at the side, you can see both chips as they are found on the card prior to any modification; with the AV7110 processor on the left and the, completely visible, 2MByte SDRAM memory chip on the right. The area conveyed in the image is roughly equivalent to that of the face of a 1EURO coin. |
In the image at the side, you can see both chips as they are found on the card prior to any modification; with the [[TI AV711x|AV7110]] processor on the left and the, completely visible, 2MByte SDRAM memory chip on the right. The area conveyed in the image is roughly equivalent to that of the face of a 1EURO coin. |
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In performing the Mod, you will have to scratch one of the thin lines on the processor until the protective coating is removed, and then afterwards solder a thin wire on to it. Next, a second SDRAM chip has to be soldered on top of the existing one. For this step, you have to ''carefully'' bend the pins on the second SDRAM chip so that they all, except for pin 18, connect 1:1 to the first SDRAM chip's pins. The exception, pin 18 (the /ChipSelect), has to instead be connected to the thin wire that you soldered to the processor earlier in the modification process. After these steps have been completed, and provided that a [[Firmware]] cognizant of the additional memory is made available, the processor will then be able to use the full 4Mbytes now residing onboard the card. |
In performing the Mod, you will have to scratch one of the thin lines on the processor until the protective coating is removed, and then afterwards solder a thin wire on to it. Next, a second SDRAM chip has to be soldered on top of the existing one. For this step, you have to ''carefully'' bend the pins on the second SDRAM chip so that they all, except for pin 18, connect 1:1 to the first SDRAM chip's pins. The exception, pin 18 (the /ChipSelect), has to instead be connected to the thin wire that you soldered to the processor earlier in the modification process. After these steps have been completed, and provided that a [[Firmware]] cognizant of the additional memory is made available, the processor will then be able to use the full 4Mbytes now residing onboard the card. |
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[[Image:Memory_Mod_Pic2.jpg|thumb|right|The AV7110 and SDRAM chips after the completed modifications to the board]] |
[[Image:Memory_Mod_Pic2.jpg|thumb|right|The AV7110 and SDRAM chips after the completed modifications to the board]] |
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*Step1: carefully bend the pins of the new |
*Step1: carefully bend the pins of the new SDRAM chip, i.e. by pressing the chip on a surface. You have to bend all pins except pin 18 CS (the 8th pin of the bottom lne, starting from the right). Have a look at the picture. |
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*Step2: solder the second SDRAM chip onto the top of the existing one. Solder the pins of the new chip on the pins of the old one. Ensure that you have all pins connected and no short circuits. |
*Step2: solder the second SDRAM chip onto the top of the existing one. Solder the pins of the new chip on the pins of the old one. Ensure that you have all pins connected and no short circuits. |
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*Step3: carefully scratch through the protective coating of the AV7110 to get the coating removed from the wire. As you can see at the picture there are 6 round areas, the wire beneath the sixth with the small step is the one we need. Please do not scratch deeply as it would make it impossible to solder on that line. If you see the copper shining it's enough. |
*Step3: carefully scratch through the protective coating of the [[TI AV711x|AV7110]] to get the coating removed from the wire. As you can see at the picture there are 6 round areas, the wire beneath the sixth with the small step is the one we need. Please do not scratch deeply as it would make it impossible to solder on that line. If you see the copper shining it's enough. |
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*Step4: soldering to the line |
*Step4: soldering to the line |
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*Step5: Connect it to the pin 18 of the SDRAM. Use a very thin wire of approx 0.1mm diameter. |
*Step5: Connect it to the pin 18 of the SDRAM. Use a very thin wire of approx 0.1mm diameter. |
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==List of suitable SDRAM chips== |
==List of suitable SDRAM chips== |
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This list may be imcomplete. |
This list may be imcomplete. |
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The AV711x needs 3.3Volt IO-Ports, therefore a 3.3Volt SDRAM in TSOPII packaging is needed. |
The [[TI AV711x|AV71x]] needs 3.3Volt IO-Ports, therefore a 3.3Volt SDRAM in TSOPII packaging is needed. |
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Some of that chips are on old graphics boards. |
Some of that chips are on old graphics boards. |
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Revision as of 22:52, 6 January 2008
Memory Mod refers to upgrading a, so called, "full-featured" DVB card equipped with 2MByte SDRAM to 4MByte of SDRAM by means of placing another memory chip over an existing chip. The idea for this modification was introduced by Oliver Endriss.
The Idea
"Full-featured" DVB cards are equipped with a 2 MByte SDRAM chip. Using the Linux DVB drivers, OSD memory space is limited to approx. 80 KBytes. Therefore, it is not possible to have a full-screen, 256 color OSD when using VDR. However, the onboard AV7110/7111 MPEG-2 Decoder used by these cards is able to handle/address two 2MByte SDRAM chips. Doubling the amount of addressable memory onboard these cards would effectively resolve the limitation outlined above and, hence, users could gain a full-screen 256 color OSD in VDR. Additionally there would be more space for the video buffers. Given the obvious benefit, why not add the second one?
The Modification
The chip select for the second SDRAM chip is not available on the pcb itself, so the AV7110 processor and the memory chip have to be modified.
In the image at the side, you can see both chips as they are found on the card prior to any modification; with the AV7110 processor on the left and the, completely visible, 2MByte SDRAM memory chip on the right. The area conveyed in the image is roughly equivalent to that of the face of a 1EURO coin.
In performing the Mod, you will have to scratch one of the thin lines on the processor until the protective coating is removed, and then afterwards solder a thin wire on to it. Next, a second SDRAM chip has to be soldered on top of the existing one. For this step, you have to carefully bend the pins on the second SDRAM chip so that they all, except for pin 18, connect 1:1 to the first SDRAM chip's pins. The exception, pin 18 (the /ChipSelect), has to instead be connected to the thin wire that you soldered to the processor earlier in the modification process. After these steps have been completed, and provided that a Firmware cognizant of the additional memory is made available, the processor will then be able to use the full 4Mbytes now residing onboard the card.
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Warning !!! | |
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This modification is only for experienced people having knowledge and experience with SMD parts. It involves work upon intricate structures around 1/10 mm in size. Any failures with handling these parts or damage to the nearby surfaces of the card may be risky for its overall health! If you undertake this modification, we take no responsibility for any damage caused or which may be incurred to your card through the process. You proceed entirely at your own risk |
- Step1: carefully bend the pins of the new SDRAM chip, i.e. by pressing the chip on a surface. You have to bend all pins except pin 18 CS (the 8th pin of the bottom lne, starting from the right). Have a look at the picture.
- Step2: solder the second SDRAM chip onto the top of the existing one. Solder the pins of the new chip on the pins of the old one. Ensure that you have all pins connected and no short circuits.
- Step3: carefully scratch through the protective coating of the AV7110 to get the coating removed from the wire. As you can see at the picture there are 6 round areas, the wire beneath the sixth with the small step is the one we need. Please do not scratch deeply as it would make it impossible to solder on that line. If you see the copper shining it's enough.
- Step4: soldering to the line
- Step5: Connect it to the pin 18 of the SDRAM. Use a very thin wire of approx 0.1mm diameter.
- Step6: Fix the thin wire and check the connection again
A completed modification should look similar to the results shown in the image at the side.
List of suitable SDRAM chips
This list may be imcomplete. The AV71x needs 3.3Volt IO-Ports, therefore a 3.3Volt SDRAM in TSOPII packaging is needed. Some of that chips are on old graphics boards.
| Producer | Part Name | Informations |
| ESMT/EliteMT | M12L16161A-7T | homepage datasheet |
| EtronTech | EM636165TS-8 | homepage datasheet |
| Samsung | K4S161622E-TC80 | homepage datasheet |
| Goldstar | GM72V161621 |
Software Requirements
DVB driver with 4MB support and Firmware 261c or newer.
External Links
| [1] | vdrwiki:osdtest256-plugin | Plugin for testing of modded cards |
| [2] | vdrwiki:text2skin-plugin | plugin for loading of skins |
| [3] | http://www.rightchoiceelectronics.com/cr.html | Reference list with different ICs. Needed: 1Mx16 SDRAMs. |
| [4] | http://www.pcstats.com/ramfinder.cfm | RamFinder - Infos about RAM-ICs |
| [5] | http://www.wolfsoft.de | DVB Card Upgrade 2MB->4MB (~45 Euro) bzw. SDRAM (5,00+9,70)Euro |