Saw the Undertones at the Top Rank in 1980, my second ever gig. First had been Sham69 at the same venue a few weeks earlier. About 800 skinheads fought with a couple of hundred punks all night, and the under age Herberts like us (jeans and Harringtons) tried to keep out of the way. The bouncers searched everybody thoroughly on the way in and then just protected the bar. Sham's battle hardened roadies protected the stage and their gear, so the dance floor was a free for all. Seen some football shit in the 80s and got a hiding a couple of times, but I've never been as scared as that night.
IIRC, Sheffield was the 2nd date of about 20. The tour was abandoned after just 4 gigs. The positive thing was that the Undertones made me realise gigs could actually be fun!
Another punk(ish) band with black lads;