If a Colour Classic with OS 7.6.1 can control a CD burner, which it can, I can think of no reason why a PB 540c cannot, given the approriate System/OS and software. Nonetheless, I haven't asked my PB 540s (stock or upgraded) to do so, I admit.
That said, however, for an external burner you are going to need an HDI-30M/CN-50M cable anyway, so why not use your 7100 to install OS 8.0 in SCSI Disk Mode instead of waiting for a CD-ROM capacity? You will still need an HDI-30 (30-pin, not 29-pin) cable, but with DB-25M instead of CN-50M at the 7100's end. Because the 540c will be seen by the 7100 as just a dumb external HDD, you will need to be careful to choose an installation 'for any Mac' to ensure that it gets the PB-specific software as well as System and Applications. It's a straightforward process, however.
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That said, however, for an external burner you are going to need an HDI-30M/CN-50M cable anyway, so why not use your 7100 to install OS 8.0 in SCSI Disk Mode instead of waiting for a CD-ROM capacity? You will still need an HDI-30 (30-pin, not 29-pin) cable, but with DB-25M instead of CN-50M at the 7100's end. Because the 540c will be seen by the 7100 as just a dumb external HDD, you will need to be careful to choose an installation 'for any Mac' to ensure that it gets the PB-specific software as well as System and Applications. It's a straightforward process, however.
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