Difference between revisions of "MASTECH MAS345"

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* Serial port settings: '''600''' baud, '''7n2''', '''DTR on'''
* Serial port settings: '''600''' baud, '''7n2''', '''DTR on'''
* Every time the host sends a (any?) character to the DMM (the vendor software sends '''D'''/'''0x44'''), it returns '''14 ASCII bytes''' containing the measurement value and so on. The documentation states that a request interval of >= 1 second is "required for stable measuring data from meter".
* Every time the host sends a (any?) character to the DMM (the vendor software sends '''D'''/'''0x44'''), it returns '''14 ASCII bytes''' containing the measurement value and so on. The documentation states that a request interval of >= 1 second is "required for stable measuring data from meter".
* Example packets: '''DC -000.0  V\r''', '''AC  00.00  A\r''', '''CA  0.071  nF\r'''


{| border="0" style="font-size: smaller" class="alternategrey sortable sigroktable"
Packet format:
 
{| border="0" style="font-size: smaller" class="alternategrey sigroktable"
|-
|-
!Byte(s)
!Byte(s)
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|-
|-
| 1-2
| 1-2
| '''Measuring mode''' ('''DC''', '''AC''', '''OH''', '''CA''', '''TE''', ...)
| '''Measuring mode''' ('''DC''', '''AC''', '''OH''', '''CA''', '''TE''', '''DI''', ...)


|-
|-
Line 66: Line 67:
| 14
| 14
| '''Carriage return''' ('''13'''/'''0x0d''')
| '''Carriage return''' ('''13'''/'''0x0d''')
|}
Example packets:
{| border="0" style="font-size: smaller" class="alternategrey sigroktable"
|-
!01
!02
!03
!04
!05
!06
!07
!08
!09
!10
!11
!12
!13
!14
|-
| D
| C
|
| -
| 0
| 0
| 0
| .
| 0
|
|
|
| V
| \r
|-
| A
| C
|
|
| 0
| 0
| .
| 0
| 0
|
|
|
| A
| \r
|-
| C
| A
|
|
| 0
| .
| 0
| 7
| 1
|
|
| n
| F
| \r
|-
| O
| H
|
|
|
| O
| .
| L
|
| M
| O
| h
| m
| \r


|}
|}

Revision as of 00:33, 7 July 2012

The MASTECH MAS345 is a 3999 counts, CAT II handheld digital multimeter with RS232 connectivity.

It is also sold under the names Velleman DVM345DI, McVoice M-345pro, and Sinometer MAS345.

Manual: Original version (2008), German version from ELV (2002)

Software: "DMM VIEW" version 2.0 (from ELV; for Win98/NT/ME/2000/XP; supports MAS343, MAS344, MAS345, M9803R)

See MASTECH MAS345/Info for more details about the device.

Hardware

Multimeter:

  • Main chip: MASTECH Japan M343-01 F0951D174 (80 pins, 16 + 16 + 24 + 24)
  • ?: ST 74HC4060 N00U732
  • ?: Texas Instruments 12AL9JM 0P07CP
  • ?: GC7555AP AA7057HS
  • ?: Sharp B B5 PC817
  • ?: Sharp B B6 PC817
  • Crystal: ca. 32kHz
  • Fuse: 15A/250V (6x30mm) (for the 10A jack; interestingly the PCB silkscreen says "20A" for that jack)

RS232 cable:

  • TODO.

Photos

TODO.

Protocol

The protocol is (partially) documented in the vendor software's "Help" window (seems to apply to MAS343, MAS344, and MAS345; the M9803R protocol is different).

  • Serial port settings: 600 baud, 7n2, DTR on
  • Every time the host sends a (any?) character to the DMM (the vendor software sends D/0x44), it returns 14 ASCII bytes containing the measurement value and so on. The documentation states that a request interval of >= 1 second is "required for stable measuring data from meter".

Packet format:

Byte(s) Description
1-2 Measuring mode (DC, AC, OH, CA, TE, DI, ...)
3 Always a space (?)
4 Sign ('-' or ' ', i.e. a minus or a space)
5-9 Decimal point and current measurement value (Examples: 10.00, 0L, 3.999)
10-13 Unit (Examples: V, mV, A, mA, kOhm, MOhm, nF, ...)
14 Carriage return (13/0x0d)

Example packets:

01 02 03 04 05 06 07 08 09 10 11 12 13 14
D C - 0 0 0 . 0 V \r
A C 0 0 . 0 0 A \r
C A 0 . 0 7 1 n F \r
O H O . L M O h m \r

Resources

TODO.