สำนักงานราชบัณฑิตยสภา

ซอฟต์แวร์ระบบส� ำหรั บแผงวงจรไมโครคอนโทรลเลอร์เพื่ อการเรี ยนรู้ 168 The Journal of the Royal Institute of Thailand Vol. 38 No. 3 July-Sep 2013 - 23 - ; Page 11 JZ E_MIP ;no numeric => <sp>/<cr> MOV BYTE PTR[SI],DL ;substitute received EX_GNA: INC SI ;next mem addr JMP DO_LYN ;repeat mem display E_MIP: CMP AL,20H ;is rcvd data a <sp>? JZ EX_GNA ;yes, data not to change JMP GET_COM ;not <sp> (may be <cr>) ; ********* AUXILIARY ROUTINES ********* ;Routine to initialize 8253, 8251 & 8255 chips IN_IT PROC NEAR ... (see text of the article) ... IN_IT ENDP ;Routine to send a blank char to display on PC BLANK PROC NEAR ... (see text of the article) ... BLANK ENDP ;Routine to scroll up display by one line CRLF PROC NEAR ... (see text of the article) ... CRLF ENDP ;Routine to convert hexadecimal number to ascii HTOA PROC NEAR ... (see text of the article) ... HTOA ENDP ;Routine to convert lower nibble of AL to ascii & display it A_BIAS PROC NEAR ... (see text of the article) ... A_BIAS ENDP ;Routine to convert & output DX data to 4 ascii chars H_OUT PROC NEAR ... (see text of the article) ... H_OUT ENDP ; Page 12 ;Routine to test 8251 for TxRDY and send char in AL to PC C_OUT PROC NEAR ... (see text of the article) ... C_OUT ENDP ;Routine to convert small letter in AL to capital letter CH_CASE PROC NEAR ... (see text of the article) ... CH_CASE ENDP ;Routine to display '?' & give audible beep when error occurs ERROR PROC NEAR ... (see text of the article) ... ERROR ENDP ;Routine to check 8251 for RxRDY and read a char into AL C_IN PROC NEAR ... (see text of the article) ... C_IN ENDP ;Routine to check C_SUM data for zero, if not, send err message CHK_SUM PROC NEAR ... (see text of the article) ... CHK_SUM ENDP ;Routine to read 2 chars via ser port & convert to 2 hex digits GET_BYT PROC NEAR ... (see text of the article) ... GET_BYT ENDP ;Routine to read 4 chars via ser port and output them in AX GET_WRD PROC NEAR ... (see text of the article) ... GET_WRD ENDP ;Routine to convert ascii char (0-9, A-F) to 4-bit binary in AL CON_V PROC NEAR ... (see text of the article) ... CON_V ENDP