xrbrevin

feel free to explain if you wish to help

LDW and California Access drives used a 5v & 12v DC combined power supply but ive never heard of a 1050 converted to this. you can buy generic power supplies with the above output voltages - they are intended to power IDE hard drives but i suppose they can be used as they have decent amp output anyone fancy a try?

the 5200 can run the game because the CPU only addresses the ROM chip inside the cart, not the system RAM. this ROM chip permanently contains the whole game code. the CPU processes the code instructions as normal - memory locations in the code are directed to the ROM chip in the cart. Consoles dont need much system memory (RAM) because the individual cartridges provide the memory - in ROM chip form. conversely, for a tape or disk game - data is slowly loaded into RAM piece by piece and the CPU then executes it from RAM. i think the problem you are facing is the UNOcart (im assuming) emulates the cartridge in software i.e. it visibly appears to boot as a cart but it just actually loads the game data into RAM the same as tape or disk (albeit much quicker) and unfortunately it uses RAM locations that are beyond your 16kb limit. what we need is someone with a 16k 600XL and an original Atari made ballblazer cart - i think it should work. i have the cart but my 600XL has the 64kb mod...! i hope this makes sense 😁

could be a limitation of the UNOcart? i know "Ultimate Cart" and "The!Cart" emulate cartridges specifically. i wonder if UNOcart is primarily for xex files?

user tf_hh makes a parallel device called "sys-check" that among other things, allows 512kb RAM: https://atariage.com/forums/index.php?app=core&module=system&controller=redirect&url=http://www.van-radecke.de/STUFF/tfhh_HW_info.pdf&key=7abde61bdfe11b10a58d3b28faddc817a6422a6eec62cefa8702ebc1b2ad10b4&resource= in reference to running a larger cart file on a 16k 600XL, the CPU is still capable of addressing 64kb so if you can find the right file type for the game, the 600XL should address/map the UNOcart directly and not use RAM try these in the UNOcart Ballblazers.zip

have you tried a different SIO cable or can you test that cable with another device?

if i recall it should spin the disk motor but im not sure maybe it also does a stepper 'chug' periodically.. 🤔 the rpm is displayed real time allowing you to adjust the blue trimpot i will dig out one of mine later on and remind myself

several computer manufacturers did something similar back in the day. they found they could reduce production costs and outsourcing by lowering the chip count - achieved by building as many glue logic chips as possible into a single unit. i wondered if the gains/benefits were stifled in order to maintain 100% compatibility with the original 'bloated' design?

ive had drives fail the stop/start test and the stepper test but they still load disks ok sure its nice when the drive passes all diags but i find that the main ones that stop disks loading are the RPM and zero sensor

if the drive is unmodded then its worth recalibrating the RPM for info, modded drives can give false readings

here be the 1050 diagnostic .atr file 1050 Disk Diagnostics.atr connect and set 1050 to D1. insert any dos disk but power it off boot the .atr from Aspeqt (or similar) disable Aspeqt and power up the 1050 run the tests

games that dont require analogue input can be played with a modded sega megadrive/genesis controller - relatively easy to do. games that do require analogue input can be played with a modified neogeo controller - but the mod is more gnarly to perform

have you done a continuity test on the power caps in situ? i had a small electrolytic cap in a 1050 cause power on failure due to it becoming a dead short. C70 if i recall...

burn your own if you have an EPROM burner

sweet! many thanks 😁