|
|
Post by zap on Mar 16, 2016 0:16:04 GMT
Burst mode can be used in c64 mode...
You can change from single sided mode to double sided mode even in c64 mode using "U0>M1" and "U0>M0"
Example: OPEN1,8,15,"U0>M1":CLOSE1 Use this command in C64 mode... Then try to format the drive in C64 mode it should format as a double sided disk will it do this in C64 mode ? if so the issue is not burst mode but a c128 issue... Just a quick thought.
And if i had read all your posts i would have seen you already tried this.... OOpps
In c64 mode try to copy a couple of programs over to your newly formatted double sided drive and run one of them in C64 mode, does this work in c64 mode is so the burst mode is working i would think and the problem is else where.
zap
|
|
|
|
Post by donno128 on Mar 18, 2016 6:59:47 GMT
Forcing C128 mode 1571 into 1541 mode via OPEN 15,8,15, "U0>M0";CLOSE 15
will do the trick, that is, disable burst mode. If you try loading a large program after issuing that you will see it takes a lot longer,
"like a 1541 on a C64 instead of 1571 in 128 mode".
The Jim Herne files about the 1571 were must haves for me.If they're not still up I believe
hydrophilic has a link on his h20 obsession page.
Since you can't use 1541 in 128 mode with "u0>m0", your problem may well involve your burst mode.
|
|
|
|
Post by donno128 on Mar 18, 2016 7:45:01 GMT
Burst mode can be used in c64 mode... You can change from single sided mode to double sided mode even in c64 mode using "U0>M1" and "U0>M0" Example: OPEN1,8,15,"U0>M1":CLOSE1 Use this command in C64 mode... Then try to format the drive in C64 mode it should format as a double sided disk will it do this in C64 mode ? if so the issue is not burst mode but a c128 issue... Just a quick thought. And if i had read all your posts i would have seen you already tried this.... OOpps In c64 mode try to copy a couple of programs over to your newly formatted double sided drive and run one of them in C64 mode, does this work in c64 mode is so the burst mode is working i would think and the problem is else where. zap That just enables 1571 mode using both sides, 1328 blocks available. Burst mode is not enabled by OPEN 15,8,15,"U0>M1":CLOSE 15 in 64 mode. You can make a hardware modification to use it that way if you wish. VIC whiz Pasi did this and released plans IIRC. |
|
|
|
Post by designcraft on Mar 18, 2016 11:02:40 GMT
I tried in C64 mode: wrote a BASIC prg to fill up space with a seq file, and it is working. Saved and can read after from both sides in c64 mode.
I also tried piggyback some IC-s at the serial port, to find faulty logic ic-s.
When I at the 74LS14 (U16), I got the DIRECTORY command, and load"$" working in C128 mode!
BUT just exactly one substitute ic works, if i try another sn7414 form a batch than not working again...
So maybe the piggybacked plus ic is faulty and that disabled the fast serial mode?
Interesting, the drive work in 1541 mode (with plus ic at sn7414) at power on. When i list the directory, i get 0 block free, but now i can do "u0>m1" and that way i can see the whole disk,
and can load data from both sides! By the way, the operation not so fast, so i think that it work in double sided mode, but not with fast serial.
The question is: what should I do now?.. How can I repair the fast serial mode, or how can i let the hardware start in 1541 mode in C128?
|
|
|
|
Post by donno128 on Mar 18, 2016 15:25:47 GMT
Software solutions are not really acceptable here I think. You could make an autoboot disk with the boot file containing the u0>m0 but I suspect autoboot doesn't work correctly. Or make a disk with OPEN15,8,15,"U0>M0":CLOSE15 as the first program and run with shift/runstop. I guess you don't have an extra 1571 drive to use as unit 9 and see if burst mode works with it in 128 mode. I think you have to find and correct the hardware failure in order to fix it and that's beyond what I do. I really don't know if installing JiffyDos would help, same with using WarpSpeed128 or another cartridge. Have you tried Hydro's SJ128?
I know you already have one but...
I dislike the 128DCR precisely because of the internal drive. It IS neat looking and takes up less space and comes with 64k video memory installed but I have had more than two DCRs with internal 1571 problems and just avoid them now. They seem to me to be overrated compared to the flat 128 and you can't even power on with the drive off.
|
|
|
|
Post by robertb on Mar 19, 2016 6:04:30 GMT
They seem to me to be overrated compared to the flat 128 and you can't even power on with the drive off. Well, you can install a switch to turn off power to the drive. Writing from the San Jose, California area, Robert Bernardo Fresno Commodore User Group www.dickestel.com/fcug.htm |
|
|
|
Post by zap on Mar 22, 2016 1:20:18 GMT
I like the Flat C128 over the C128Dcr however this is just a personal opinion and have three c128dcr and one older C128D with no issues.. My main Commodore is a C-128 flat for C-128 and C-64 software i run. I have however een unlucky with SX64 internal drives but repairable on each occasion they have failed. Always worth a read cbm8bit.com/articles/ray-charlsen/article26 Common C-128 chip faults. Also worth the read.. cbm8bit.com/articles/ray-charlsen/article20 Common 1571 and 1571 dcr faults.. zap. |
|
|
|
Post by designcraft on Mar 23, 2016 17:33:33 GMT
I made it!!!  After countless hours and swapped ICs, the drive is working again... or first time really. I desoldered and socketed numerous chips... What i replaced: 7414, 7406 (x2) chips, socketed and swapped the two 65c22 VIA, and checked the two 6526 VIA, but these cannot checked with the piggybacking technique! So I read and read more troubleshooting tutorials and I read the SAMS book for C128DCR and one thing was important: 7. Serial Port Serial Port (CN6) works only with peripherals that work In Slow mode (like Commodore 1541 Disk Drive), does not work In Fast mode (with 1571 Disk Drive). Check CIA1 IC U1. So I socketed that 6526A CIA, and the drive works again in C128 mode too!!! Whoa... One problem remains after all, and this is a disk ID error. When I change disks there is no motor sound, so the sensor isn't working. No motor sound too when I first insert a diskette. I see that sensor, and i made some photos of it with my phone camera (the camera sensor is see the IR light from the led), and there is IR light, so maybe another IC is the problem?... Thanks very much for the help for all. |
|
|
|
Post by designcraft on Mar 24, 2016 0:28:01 GMT
The disk Id error is solved too. I measured the signal from the write protect sensor to the 74LS14 inverter and found it to be good. solution: I half-cut one trace on the pcb when socketed the 7406 IC... found it after I followed the sensor path from the 7414 pin 10 to the 65c22 pin 39. A thin wire soldered between the two pin and voila! Everything is in working order!  Not beautiful but good enough... One happy C128 DCR owner. |
|
|
|
Post by donno128 on Mar 24, 2016 13:47:17 GMT
Perseverance wins! Congrats on being able to enjoy your DCR! What's next? |
|
Not beautiful but good enough...