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Elite on the BBC Micro

Utility routines: CLYNS [Elite-A, Parasite]

Name: CLYNS [Show more] Type: Subroutine Category: Utility routines Summary: Clear the bottom three text rows of the mode 4 screen by sending a clr_line command to the I/O processor
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * EQSHP calls CLYNS * JMTB calls CLYNS * TITLE calls CLYNS * TT102 calls CLYNS * TT219 calls CLYNS * cour_buy calls CLYNS * hm calls CLYNS * menu calls CLYNS * n_buyship calls CLYNS * qv calls CLYNS

Returns: A A is set to 0 Y Y is set to 0
.CLYNS LDA #%11111111 \ Set DTW2 = %11111111 to denote that we are not STA DTW2 \ currently printing a word LDA #20 \ Move the text cursor to row 20, near the bottom of STA YC \ the screen JSR TT67 \ Print a newline, which will move the text cursor down \ a line (to row 21) and back to column 1 LDY #1 \ Move the text cursor to column 1 STY XC DEY \ Set Y = 0, so the subroutine returns with this value LDA #&84 \ Send command &84 to the I/O processor: JMP tube_write \ \ clr_line() \ \ which will clear the bottom three text rows of the top \ part of the screen and return from the subroutine \ using a tail call