The 128MB SDRAM module for MiSTer FPGA was acquired in AliExpress, shop LICHIFIT-Z6H Electrics Store for use on my MiSTer FPGA, that I have already shown in the first two parts of this series of articles:
- Building a MiSTer - Part 1: Terasic DE10-Nano and IO Board w / Noctua NF-A4X10-FLX 5V - via Direct Shipping
- MiSTer USB Hub - MiSTer Add-ons via Direct Shipments - Building a MiSTer - Part 2
The Módulo SDRAM is used by the vast majority of cores do MiSTer FPGA. Few work without it, and even in these cases its use is recommended to avoid possible problems.
A placa DE10-Nano, base do MiSTer, has 1GB of DDR3 memory. But, its access by the FPGA has a certain latency, which hinders its use when implementing video game systems, arcades and computers, that should work with great accuracy and minimum latency. Remember that old systems, like second to fourth generation video games, had direct access to the cartridge ROMs, and read data from them all the time.
The solution created by the developers was to add an SDRAM module to the input and output pins of the board. Initially 32MB modules were used, but with the launch of core from Neo Geo, 128MB modules became the most used, to accommodate the ROM images of the larger capacity cartridges.
Therefore, as soon as i decided to start assembling my MiSTer i already tried to put the SDRAM memory among the first items i would buy.
Choice of SDRAM for 128 GB from AliExpress
The option to purchase the 128MB SDRAM module for MiSTer FPGA on AliExpress it was because of the attractive price and to avoid the use of order redirection, since AliExpress sellers already declare low values by default to protect us from institutionalized theft that is practiced by the IRS.
At the time there was only one vendor for the modules, now there are several, but apparently the source is the same for everyone.
Of course, the reliability issue weighed in on my choice. I could have bought at MiSTer Add-ons, whose seller already has a reputation in selling parts to MiSTer, is accessible and speaks English natively. But MiSTer has an excellent core to test the SDRAM and the AliExpress has the buyer protection program in case of any defect. So I decided to risk.
Unboxing, Installation and testing
The COVID-19 pandemic ended up quite hindering the arrival of my 128MB SDRAM module for MiSTer FPGA. First it was the seller who did not have the product on hand and the factories were stopped in China. This delayed sending the package by more than a month.
With the package sent, the pandemic had already arrived in Europe, and then it was time for delays in sending from China to Sweden and from Sweden to Brazil. Even AliExpress has neglected Swedish mail and used Hong Kong mail for its standard shipments in recent packages.
Added all delays, the purchase made at the end of January ended up arriving here only at the end of May, after almost four months. But it was worth the wait.
The 128MB SDRAM module for MiSTer FPGA didn't come there very well protected. Just a plastic bag and the plastic envelope. Missing a box, a styrofoam or bubble wrap. But it arrived intact.
The PCB is blue, and has the inscriptions: “SD-RAM XS-D v2.5 (C) Alexey Melkinov”. This shows that this is the latest revision of the plaque and that the Chinese kept the credits of the creator of the project. Most likely the origin is the same factories that they manufacture for the other sellers.
The memory chips are from the Alliance brand, and bring the inscription “AS4C32M168B-7T1N”. The welds also looked good. Ultimately, all right externally with the little module. Time to install it and test it.
Check out the photos and the video of the unboxing, installation and testing of 128MB SDRAM module for MiSTer FPGA:
Installation is trivial, simply insert the module into the appropriate pins in the DE10-Nano. When starting MiSTer, it already detects the module and so I used the core memtest to test it. The test indicated that it supports a frequency of 140 MHz, more than enough for MiSTer, which requires no maximum 130 MHz, us cores more demanding. The SDRAM test was broadcast live on our Youtube channel:
After more than an hour of testing to make sure the 128MB SDRAM module for MiSTer FPGA it was perfect, I went for the tests with the cores of CPS1, Neo Geo, NES, Master System, Super Nintendo, Game Boy, and several others. Everything working perfectly, as can be seen in MiSTer's playlist on our Youtube channel:
These are the package tracking information obtained on the website of the AliExpress:
2020.05.27 16:07 (GMT-7): Delivery successful 2020.05.21 09:31 (GMT-7): Cleared customs 2020.05.19 08:59 (GMT-7): Accepted by Last Mile Carrier 2020.03.24 09:36 (GMT-7): Departed country of origin 2020.03.20 16:12 (GMT-7): Shipment accepted by airline 2020.03.19 14:19 (GMT-7): Shipment left country of origin warehouse 2020.03.18 23:54 (GMT-7): Shipment at country of origin warehouse 2020.03.18 23:24 (GMT-7): Shipment dispatched
And these are the information obtained on the site of the station:
27/05/2020 16:07 [REMOVED] / SP Object delivered to the recipient 27/05/2020 10:40 [REMOVED] / SP object out for delivery to the recipient 26/05/2020 07:44 INDAIATUBA / SP Objeto encaminhado de Unidade de Tratamento em INDAIATUBA / SP for distribution Unit in [REMOVED] / SP 21/05/2020 09:56 CURITIBA / PR Objeto encaminhado de Unidade de Distribuição em CURITIBA / PR for Treatment Unit in INDAIATUBA / SP 21/05/2020 09:54 CURITIBA / PR finalized Customs supervision 19/05/2020 09:22 CURITIBA / PR Objeto recebido pelos Correios do Brasil Informar nº do documento para a fiscalização e entrega do seu objeto. Click here My Imports 09/04/2020 13:21 SWEDEN / Objeto encaminhado de País em SUECIA / countries in International treatment unit / BR Informar nº do documento para a fiscalização e entrega do seu objeto. Click here My Imports 09/04/2020 10:51 SWEDEN / Objeto recebido na unidade de exportação no país de origem Informar nº do documento para a fiscalização e entrega do seu objeto. Click here My Imports 09/04/2020 10:27 SWEDEN / Objeto postado Informar nº do documento para a fiscalização e entrega do seu objeto. Click here My Imports
This is the table-summary of purchase:
|Product Name:||128MB SDRAM module for MiSTer FPGA|
|Name Original:||1pc For MISTER FPGA SDRAM Board Module 128MB for Atari 2600 5200 GBC GB FC SFC PCE MD NEO GEO Replacement Motherboard|
|Store:||AliExpress | Store: LICHIFIT-Z6H Electrics Store|
|Current value:||Unavailable at the store I purchased. R$ 287,53 at the cheapest store today.|
|Payment Method:||Credit Card Visa International|
|Shipping Type:||Aliexpress Standard Shipping|
|Shipping Fee:||R$ 10,59|
|Package Home Country:||China|
|Time in Transit:||70 days|
|Declared content:||SDRAM board|
|Type Marked Content:||Others|
|Declared Value:||USD $11.54|
With that I took another step to leave my MiSTer FGPA full, the way I always wanted. Indeed, in functionality it is already complete. Now only the case for him to be very beautiful and protected, but he is already on his way. 🙂