Welch Allyn TM 262 Auto Tymp - User Manual - Manual (Page 75)

Revised 4/11/08 5-9
RS-232 Interface
Audiometry test results record
Notes
1. “uChar” & “sChar” designate unsigned and signed characters respectively, single bytes
represented in Hexadecimal by two ASCII characters.
Example: OxE9 is sent as: “E”, “9”
2. “ulnt: and slnt” designate unsigned and signed 16-bit integers respectively, expressed in
HiByte/ LowByte sequence by four Hex ASCII characters.
Example: OxE196 is sent as: “E”, “1', “9”, “6”
3. Tympanometry compliance values are stored in the record scaled by 64. To convert to cm 3 ,
divide by 64.
Example: Tymp Data[0] = “4”, “2” = 0x42=66 decimal scales X64 = 66/64 = 1.0-3 cm 3
4. Reflex compliance values are stored in the record scaled by 256: To convert to cm 3 , divide
by 256.
Character
Number Number of
Characters
Data Type Field Name Field Description
1 1 ASCII Start of record “.”
2 1 ASCII Record Type “y”
3 1 ASCII Record Sequence Number “0” to “9”
4 1 ASCII Record Index Number “1” to “8”
5 1 ASCII Total Record Number “1” to “8”
6
11
13
5
2
4
ASCII
uChar
sint
Reserved Ear
HL Threshold 125 Hz
Either the RIGHT ear
is selected OR the
LEFT ear is selected.
Both ears selected or
no ears elected is
invalid.
-10 to +100 dB HL x 2
NR = Any value in the
range of 231 to 450
NT = 32,768 (0x8000
Hexadecimal)
: : : : :
53 4 sint HL Threshold 8000 Hz -10 to +100 dB HL x 2
NR = Any value in the
range of 231 to 450
NT = 32,768 (0x8000
Hexadecimal)
57 2 uChar Checksum The hexadecimal sum
of characters 1 to 56
59 2 ASCII Package Terminator “CR”, “LF”