Atari 800XL SDrive help

[unebonnevie]

hi,

 

I managed to build the circuit of the SDrive at http://raster.infos.cz/atari/hw/sdrive/sdriveen.htm.

 

When the board is plugged into the Atari 800XL's SIO port, only the GREEN led is ON and it stays on EVEN I have made sure to insert the SD card in.

 

What does the SENSE connection to the SD card connector in the schematic mean?  Does it mean that the firmware would try to detect if the SD is plugged in?  If so, is the sense supposed to HIGH or LOW once the SD card is plugged in?  My SD card does not have the sense pin.  So, I simulate that with a jumper to 5V or GND.  I should jump to GND to say that the SD is plugged in, that is, to help the firmware to determine that the SD has been plugged in?

 

Thanks for any tips!

[TGB1718]

Assuming you have checked all the connections and verified the control program has been uploaded 

to the ATMega chip, the usual problems with these type of devices is the SD card your using, it may be

a compatibility issue,  most find SanDisk SD cards are the most reliable.

[_The Doctor__]

Can't hurt to reprogram the atmega as well, double check your work and sio wiring... use that dmm/or other meter

[a8isa1]

On 8/1/2021 at 4:18 AM, unebonnevie said:

hi,

 

I managed to build the circuit of the SDrive at http://raster.infos.cz/atari/hw/sdrive/sdriveen.htm.

 

When the board is plugged into the Atari 800XL's SIO port, only the GREEN led is ON and it stays on EVEN I have made sure to insert the SD card in.

 

What does the SENSE connection to the SD card connector in the schematic mean?  Does it mean that the firmware would try to detect if the SD is plugged in?  If so, is the sense supposed to HIGH or LOW once the SD card is plugged in?  My SD card does not have the sense pin.  So, I simulate that with a jumper to 5V or GND.  I should jump to GND to say that the SD is plugged in, that is, to help the firmware to determine that the SD has been plugged in?

 

Thanks for any tips!

I did some quick testing (after doing some not quick repairs to my classic SDrive).

 

Green LED isn't a power indicator per se.  It is normally turned off until there is Read activity.

 

The normal start sequence is the Green LED blinks momentarily then turns off.   The four yellow LEDs light.  Activity on the Green LED and it goes out again.  Finally yellow LED L1 is the only one lit and the SDrive menu is displayed on the screen.

 

IF the green LED lights but nothing else does I believe this means the Atmega is correctly programmed but there is something wrong with the SD card.

 

- It's not installed.

- It's not formatted FAT16.

 

IF green LED blinks and only yellow LED L1 lights then

 

- SDRIVE.ATR is not in the root of the SD card

 

If SDRIVE.ATR is corrupt then

 

- all four yellow LEDs stay lit and "BOOT ERROR"

 

I hope this helps.

 

Regards,

 

SteveS

Edited August 5, 2021 by a8isa1

[unebonnevie]

On 8/5/2021 at 12:17 PM, a8isa1 said:

I did some quick testing (after doing some not quick repairs to my classic SDrive).

 

Green LED isn't a power indicator per se.  It is normally turned off until there is Read activity.

 

The normal start sequence is the Green LED blinks momentarily then turns off.   The four yellow LEDs light.  Activity on the Green LED and it goes out again.  Finally yellow LED L1 is the only one lit and the SDrive menu is displayed on the screen.

 

IF the green LED lights but nothing else does I believe this means the Atmega is correctly programmed but there is something wrong with the SD card.

 

- It's not installed.

- It's not formatted FAT16.

 

IF green LED blinks and only yellow LED L1 lights then

 

- SDRIVE.ATR is not in the root of the SD card

 

If SDRIVE.ATR is corrupt then

 

- all four yellow LEDs stay lit and "BOOT ERROR"

 

I hope this helps.

 

Regards,

 

SteveS

Thanks, SteveS.  Yeah, I actually put in debugging statements in the code using the LED to blink, etc.  And basically it fails on fatInit(...) not finding FAT16 file system, even though I formatted my SD card as FAT, which is FAT16.  I only have ONE file on the SD card, and that is the SDRIVE.ATR.  The SDrive firmware code is atrocious ?

 

Anyway, fatInit(...) detects the SD card to be something else that is *not* FAT16 or FAT32.  It's something else.  There are many constants of filesystem type.  For sure, it's not detecting FAT16 or FAT32.  I just need to check for other types by blinking the LED for debugging.

 

My card is 1GB, which is less than the maxium 2GB requirement by SDrive.

 

I couldn't find an SD connector with the CARD DETECTED pin, so I use the below SD card breakout board.  And ground the GPIO pin on the ATMEGA8 that checks for SD card detection.

 

 

Edited August 9, 2021 by unebonnevie

[a8isa1]

On 8/1/2021 at 4:18 AM, unebonnevie said:

hi,

 

I managed to build the circuit of the SDrive at http://raster.infos.cz/atari/hw/sdrive/sdriveen.htm.

 

When the board is plugged into the Atari 800XL's SIO port, only the GREEN led is ON and it stays on EVEN I have made sure to insert the SD card in.

 

What does the SENSE connection to the SD card connector in the schematic mean?  Does it mean that the firmware would try to detect if the SD is plugged in?  If so, is the sense supposed to HIGH or LOW once the SD card is plugged in?  My SD card does not have the sense pin.  So, I simulate that with a jumper to 5V or GND.  I should jump to GND to say that the SD is plugged in, that is, to help the firmware to determine that the SD has been plugged in?

 

Thanks for any tips!

my purchased sdrive works after some sketchy repairs.

 

After 10 years my own "ghetto sdrive", no LEDs, no buttons or switches, stopped working. 

 

I don't recall ever attempting to connect the read/write pin or a sense pin.

 

What I made was a kludge. Minimum of parts and skipped some key engineering.

 

Freeduino board as a breakout board for the Atmega8. Used a crystal because I couldn't source the resonator. Skipped the load capacitors. Used zener diodes in reverse breakdown instead of voltage divider circuit. Skipped the current limiting resistors. SD breakout board may or may not have helped me there. My voltage switchers were defective so I used 2 signal diodes in series. A 3.7volts I was powering the SD card above specification.

 

Somehow it worked and continued for 10 years.

 

i've since switched SIo2pc, fujinet, Sdrive-MAX, and AVGCart.

 

Some day I will rebuild the ghetto SDrive just because I liked its simplicity with no moving parts