I cannot get a Commodore 1530 Datasette to load/save to tape

[Blacklord]

Unless you're trying this with a B500 or P500 with first (-01) revision ROMs it is working as designed. The tape code was pulled from production ROMs after April 1983 to make room for a machine language monitor. If you are trying this with a machine with the original ROM code then run a tape head cleaner on the 1530 first, then a head de-magnetizer and try it again with a high-quality but non-metal tape.

[carlsson]

It just struck me - would an early B500 have tape support that the 610 lacks? I happen to own both a B500, a CBM 610 and a 710 but never considered the B500 might have any functional benefit over the 610.

In the firmware directory on Zimmers FTP, I find the following files:

901244-01 = B500 Kernal
(where is 901244-02 ?)
901244-03b = B128/256 Kernal, old revision
901244-04b = B128/256 Kernal, new revision

901243-01 = B500 Basic Low
901243-02b = B128 Basic Low, old revision
(where is 901243-03 ?)
901243-04a = B128 Basic Low, new revision

901242-01a = B500 Basic High
901242-02b = B128 Basic High, old revision
(where is 901422-03 ?)
901242-04a = B128 Basic High, new revision #1
901242-04_ = B128 Basic High, new revision #2

However since my B500 is modified with Swedish characters, I suppose it contains the updated B128 ROMs. Would it be then possible and adviceable to downgrade it to earlier ROM versions, even if those are EPROMs just like currently installed?

[Michau]

As you saw with the IEC kernal, putting old kernal on your machine will get you the U.S. keyboard instead of Swedish.

Perhaps there would be some way to extract the machine code responsible for tape operations and put it onto our cartidge in the making?

[carlsson]

Actually the B500 has been traded to a dear collector, so it is no longer my problem. 

As for tape routines, I'm not sure if it is worth the trouble. While accessing a relatively cheap IEC style floppy drive, even if it is slow and inflexible is a good addition, I wonder how many CBM-II users today would benefit from being able to use a Datasette. Perhaps for "emergency" transfer options.