Add conversion to hPa

bme280_util.z80

@@ -90,8 +90,30 @@ delay1:
                 jr      nz,delay1
                 ret
 
-convert_to_hpa:
+convert_to_hpa:                                 ; shift the decimal point in (pressure) two places left
-                ld      a,(pressure)
+                ld      hl,pressure
+                ld      b,0                     ; count of digits ahead of the point
+find_point:
+                ld      a,(hl)
+                or      a
+                ret     z                       ; no point in the string, leave it alone
+                cp      a,2eh                   ; period
+                jr      z,found_point
+                inc     hl
+                inc     b
+                jr      find_point
+found_point:
+                ld      a,b
+                cp      3                       ; need three whole digits to shift by two
+                ret     c
+                dec     hl                      ; step back over the ones digit
+                dec     hl                      ; hl now holds the new tenths digit
+                ld      a,(hl)
+                ld      (hl),2eh                ; drop the point in two places left
+                inc     hl
+                ld      (hl),a                  ; and the saved digit after it
+                inc     hl
+                ld      (hl),00h                ; null terminate, discarding the rest
                 ret
 
 read_char_b:
@@ -141,6 +163,7 @@ print_telem_to_lcd:
                 ld      hl,temperature
                 call    print_str_to_lcd
 
+                call    convert_to_hpa
                 call    move_to_presaddr
                 ld      hl,pressure
                 call    print_str_to_lcd
@@ -202,7 +225,7 @@ move_to_tempaddr:
                 ret
 
 move_to_presaddr:
-                ld      a,0c1h
+                ld      a,0c3h
                 out     (lcd_ctrl),a
                 call    lcd_delay
                 ret
@@ -214,7 +237,7 @@ move_to_humidaddr:
                 ret
 
 clabel:         DB      'degree C',0
-plabel:         DB      'pascal',0
+plabel:         DB      'hPa',0
 hlabel:         DB      '% RH',0
 
 char_max        equ     15