1. TPS61221 :
The TPS61221 is available in EU at Farnell.com. It is cheaper than the LTC . May be it is also available at Newark.com in the USA.
2. GBA housing :
Today i have searched the net for used, cheap GameBoyColor or GameBoyAdvance and replacement housing. In Germany used GBA or GBC cost about 40€ (~55$) exclusive shipping. I think this is too expensive to disassemble the unit. I found one GBA replacement housing (~10€) and some GBA-SP-housings. I am not really happy about this and I was wondering if it is the right track to plan a replacement board with all the edge condition of the given housing.
3. Mini PCI Express connector :
I noticed a problem with the Mini PCI Express plug. The cartridge is inserted at an angle of 16 degrees and then pushed down into the holder. Of course this means the existing GBA-housing must be changed.
I fear it will not be the last problem with this project.
Now I ask myself the question : Would it be better, to construct a new gamepad board similar to the GBA, a little bit smaller, of course with a cardridge, and hobbyists build their own housing (case modding) as in the hive-project done (hive-project.de, a retro-computer-project) ?
Here's a schematic for review. Not sure how to route it all since I don't have an enclosure.
Some questions come up:
1. Can an EEPROM always live on the cartridge? I think it should. JP1 allows "dual role" for the baseboard chip.
2. How would an "idle" power switch circuit look connected to the Enable pin of the boost regulator?
I'm not exactly sure where this is headed, but I think the schematic is generic enough to suit applications.
I would really like to find a nicer chassis enclosure that has a 3.3" cutout and room for buttons. Any ideas?
Any constructive feedback on the design would be appreciated.
Hallo !
1. In the given plan is an LCD display shown, that required a special LED-driver (19.3 V and 15 mA) for the back-light.
2. An EEPROM on the card is possible. The connection could be selected as I2C(note addressing) or SPI. I prefer a boot loader on the built-in eeprom. The selection of the software is done with a menu (part of the bootloader).
4. At the moment, I calculate the power consumption of the circuit (one or two step-up booster). I have scheduled an SPI bus, as in the propeller C3 Board. At the SPI bus, a SD card, 2 x 32kB SRAM, 1MB Flash and the cartridge holder is connected. I do not know if there are any legal restrictions on the free use of the C3-SPI-bus. I have found in the documentation of the C3 board no license information. By using this bus, some of the existing software of the c3-board could be used.
The other SPI ports, LCD and touch screen, are not connected to this bus.
5. From Hammond Manufacturing, there are handheld housing with build in battery boxes. Some of the cases are distributed by Mouser.
>> 1. In the given plan is an LCD display shown, that required a special LED-driver (19.3 V and 15 mA) for the back-light.
I think you're right. I looked at this a long time. I thought the controller was providing it because of the internal backlight controls, but the spec does say input should be < 27V. I have one of these displays but haven't had a chance to try it yet.
That looks great, but is really expensive as you say. I can't find a US distributor.
>> 4. At the moment, I calculate the power consumption of the circuit (one or two step-up booster). I have scheduled an SPI bus, as in the propeller C3 Board. At the SPI bus, a SD card, 2 x 32kB SRAM, 1MB Flash and the cartridge holder is connected.
One of the reasons i'm interested in having the boot EEPROM be on the cartridge is so that it can allow any boot configuration. C3 and it's apps are interesting, but there are many more possibilities
>> I do not know if there are any legal restrictions on the free use of the C3-SPI-bus.
C3 is supposed to be a fully open source solution.
>> 5. From Hammond Manufacturing, there are handheld housing with build in battery boxes. Some of the cases are distributed by Mouser.
Yes, i've looked at many of these cases many times. Nothing really works perfect. One enclosure I do like though is RH3155 - it is thin and pocket sized but does not have a battery door.
I found a very nice, small, and cheap 36 pin connector solution today.
The Hirose ST series connectors look like "cradle" connectors used with iPODs.
I've added the connector to a hand-held Propeller product which I'll begin testing in a few weeks.
Here are some pictures. Imagine the possibilities ....
My handheld propeller project called now : Gam_Bo_Prop
Planned :
1 x propellerchip
1 x DS1338 RTC with backup battery
1 x 64kB EEProm
1 x FT232RL
1 x 2,83" LCD-display
1 x touchscreen controller ADS7846
8 buttons controlled by a decimal to BCD encoder 74HC147 (4 propeller portlines)
and a modified propeller C3 SPI-Bus with 74HC138 controlled by 3 propeller portlines
2 x 32kB SRam
2 x flash rom
1 x SD-connector without shield https://www.it-wns.de/images/dbimages/artikel_0000119_b_1.jpg
The SD-connector has two additional select lines on pin 8 and 9 for SD-modules. Because the SD-connector has an open frame you can use SD-modules thicker than 2.1mm.
A picture of the board (dimensions 115mm x 60mm) :
a picture of a sram and/or flash memory SD-module :
and a picture of a transceiver SD-module with RFM12B and chip-antenna :
Hi,
i think the first prototypes of the Gam_Bo_Prop motherboard and the two SD-modules will be ready in the first week of May. I hope it all works correct, but there will be some difficulties with the software and also the hardware. Small battery contacts and the drivers for the LCD display and the touchscreen controller cause headaches to me.
When it works correct I will publish the schematic and the layout.
Hello, the boards for the Gam_Bo_Prop arrived today. I publish a build thread in the Hive-Project Forum in German and English. All on Gam_Bo_Prop interested, please look here : http://hive-project.de/board/viewtopic.php?f=12&t=464
Hello, the boards for the Gam_Bo_Prop arrived today. I publish a build thread in the Hive-Project Forum in German and English. All on Gam_Bo_Prop interested, please look here : http://hive-project.de/board/viewtopic.php?f=12&t=464
Comments
The TPS61221 is available in EU at Farnell.com. It is cheaper than the LTC . May be it is also available at Newark.com in the USA.
2. GBA housing :
Today i have searched the net for used, cheap GameBoyColor or GameBoyAdvance and replacement housing. In Germany used GBA or GBC cost about 40€ (~55$) exclusive shipping. I think this is too expensive to disassemble the unit. I found one GBA replacement housing (~10€) and some GBA-SP-housings. I am not really happy about this and I was wondering if it is the right track to plan a replacement board with all the edge condition of the given housing.
3. Mini PCI Express connector :
I noticed a problem with the Mini PCI Express plug. The cartridge is inserted at an angle of 16 degrees and then pushed down into the holder. Of course this means the existing GBA-housing must be changed.
I fear it will not be the last problem with this project.
Now I ask myself the question : Would it be better, to construct a new gamepad board similar to the GBA, a little bit smaller, of course with a cardridge, and hobbyists build their own housing (case modding) as in the hive-project done (hive-project.de, a retro-computer-project) ?
--G
Check this for housings: http://stores.ebay.com/accessories-center/Video-Game-/_i.html?_fsub=1812161011&_sid=802338511&_trksid=p4634.c0.m322
Some questions come up:
1. Can an EEPROM always live on the cartridge? I think it should. JP1 allows "dual role" for the baseboard chip.
2. How would an "idle" power switch circuit look connected to the Enable pin of the boost regulator?
I'm not exactly sure where this is headed, but I think the schematic is generic enough to suit applications.
I would really like to find a nicer chassis enclosure that has a 3.3" cutout and room for buttons. Any ideas?
Any constructive feedback on the design would be appreciated.
Thanks.
--Steve
1. In the given plan is an LCD display shown, that required a special LED-driver (19.3 V and 15 mA) for the back-light.
2. An EEPROM on the card is possible. The connection could be selected as I2C(note addressing) or SPI. I prefer a boot loader on the built-in eeprom. The selection of the software is done with a menu (part of the bootloader).
3. I have found an ideal cardridge holder. http://de.farnell.com/samtec/mb1-130-01-ls-02-sl/mini-card-pci-e-30kontakte/dp/1753946. These are available with 20, 30, 40 and 50 contacts (edge connector) for PCB thicknesses of 0.8 mm or 1.5 mm. But they are expensive.
4. At the moment, I calculate the power consumption of the circuit (one or two step-up booster). I have scheduled an SPI bus, as in the propeller C3 Board. At the SPI bus, a SD card, 2 x 32kB SRAM, 1MB Flash and the cartridge holder is connected. I do not know if there are any legal restrictions on the free use of the C3-SPI-bus. I have found in the documentation of the C3 board no license information. By using this bus, some of the existing software of the c3-board could be used.
The other SPI ports, LCD and touch screen, are not connected to this bus.
5. From Hammond Manufacturing, there are handheld housing with build in battery boxes. Some of the cases are distributed by Mouser.
--G
I think you're right. I looked at this a long time. I thought the controller was providing it because of the internal backlight controls, but the spec does say input should be < 27V. I have one of these displays but haven't had a chance to try it yet.
>> 3. I have found an ideal cardridge holder. http://de.farnell.com/samtec/mb1-130-01-ls-02-sl/mini-card-pci-e-30kontakte/dp/1753946.
That looks great, but is really expensive as you say. I can't find a US distributor.
>> 4. At the moment, I calculate the power consumption of the circuit (one or two step-up booster). I have scheduled an SPI bus, as in the propeller C3 Board. At the SPI bus, a SD card, 2 x 32kB SRAM, 1MB Flash and the cartridge holder is connected.
One of the reasons i'm interested in having the boot EEPROM be on the cartridge is so that it can allow any boot configuration. C3 and it's apps are interesting, but there are many more possibilities
>> I do not know if there are any legal restrictions on the free use of the C3-SPI-bus.
C3 is supposed to be a fully open source solution.
>> 5. From Hammond Manufacturing, there are handheld housing with build in battery boxes. Some of the cases are distributed by Mouser.
Yes, i've looked at many of these cases many times. Nothing really works perfect. One enclosure I do like though is RH3155 - it is thin and pocket sized but does not have a battery door.
RH3155 : This housing (Hammond 1599ESGYBAT) is available at Mouser with battery box : Mouser part-number. 546-1599ESGYBAT
On connectors, I find these 2 at www.4uconnector.com
http://www.4uconnector.com/online/object/4udrawing/07863.pdf
http://www.4uconnector.com/online/object/4udrawing/02850.pdf
They are cheap but the min order quantity is 1000 pieces - not bad though if you plan to sell that many.
The Hirose ST series connectors look like "cradle" connectors used with iPODs.
I've added the connector to a hand-held Propeller product which I'll begin testing in a few weeks.
Here are some pictures. Imagine the possibilities ....
Planned :
1 x propellerchip
1 x DS1338 RTC with backup battery
1 x 64kB EEProm
1 x FT232RL
1 x 2,83" LCD-display
1 x touchscreen controller ADS7846
8 buttons controlled by a decimal to BCD encoder 74HC147 (4 propeller portlines)
and a modified propeller C3 SPI-Bus with 74HC138 controlled by 3 propeller portlines
2 x 32kB SRam
2 x flash rom
1 x SD-connector without shield https://www.it-wns.de/images/dbimages/artikel_0000119_b_1.jpg
The SD-connector has two additional select lines on pin 8 and 9 for SD-modules. Because the SD-connector has an open frame you can use SD-modules thicker than 2.1mm.
A picture of the board (dimensions 115mm x 60mm) :
a picture of a sram and/or flash memory SD-module :
and a picture of a transceiver SD-module with RFM12B and chip-antenna :
--G
i think the first prototypes of the Gam_Bo_Prop motherboard and the two SD-modules will be ready in the first week of May. I hope it all works correct, but there will be some difficulties with the software and also the hardware. Small battery contacts and the drivers for the LCD display and the touchscreen controller cause headaches to me.
When it works correct I will publish the schematic and the layout.
--G