HI Grant-Adler.
Concerning your suggestion
both the ends of the cable I think would work on my computer but I need the B plug for my piano keyboard.
I found this at Sweetwater - https://www.sweetwater.com/store/detail/USBAB15--hosa-usb-215ab-15-foot, unlike the BestBuy Cable I purchased. I think it ought to work since it is from a music site and apparently designed for piano keyboards. What do you think? Again thank you for your help.
Below are the specs for the computer and thunderbolt ports--
Model Name: MacBook Pro
Model Identifier: MacBookPro11,4
Processor Name: Quad-Core Intel Core i7
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Thunderbolt/USB4:
Thunderbolt Bus:
Vendor Name: Apple Inc.
Device Name: MacBook Pro
UID: 0x0001001701E8ED10
Route String: 0
Firmware Version: 27.1
Domain UUID: E5A6AE59-6BC4-CF54-86F1-C7EDA38F265C
Port:
Status: No device connected
Link Status: 0x101
Speed: Up to 20 Gb/s x1
Current Link Width: 0x1
Receptacle: 1
Link Controller Firmware Version: 0.15.0