INDR - Z80 instruction reference

indrInput, decrement and repeat 
Repeats IND, reading port bytes into memory downward from HL until B is zero.
2 bytes · 21/16 cycles·21 cycles for a pass that repeats, 16 for the last
SZHP/VNC ?1??1?
1 always 1
? undefined afterwards
Forms  indr  
A byte from the port at the 16-bit address contained in the BC register pair is written to the memory location pointed to by HL. Then HL and B are decremented. If B is not zero, this operation is repeated. Interrupts can trigger while this instruction is processing. Note that the carry flag may be affected, contrary to documentation. Read More
         .org 0x8000
        ld hl, 0x9000
        ld b, 2
        ld c, 0xF0
        indr
        halt