Difference between revisions of "MASTECH MAS345"
Jump to navigation
Jump to search
(TI op amp info) |
Uwe Hermann (talk | contribs) m (→Resources) |
||
| Line 191: | Line 191: | ||
** [http://www.elv-downloads.de/service/manuals_hw/45988_MAS345_Software_V20.zip "DMM VIEW" software, version 2.0] (for Win98/NT/ME/2000/XP; supports MAS343, MAS344, MAS345, M9803R) | ** [http://www.elv-downloads.de/service/manuals_hw/45988_MAS345_Software_V20.zip "DMM VIEW" software, version 2.0] (for Win98/NT/ME/2000/XP; supports MAS343, MAS344, MAS345, M9803R) | ||
* [http://www.cczwei-forum.de/cc2/thread.php?threadid=3452 cczwei-forum.de: C# software for reading DMM values] | * [http://www.cczwei-forum.de/cc2/thread.php?threadid=3452 cczwei-forum.de: C# software for reading DMM values] | ||
* [http://www.linux-magazin.de/Heft-Abo/Ausgaben/2007/08/E-Werke?category=0 Linux Magazin: E-Werke: Perl misst Stromverbrauch mit Multimeter] | |||
* [https://savannah.nongnu.org/projects/marsh mas-345/marsh: multimeter read and store] | |||
* [http://libesz.digitaltrip.hu/mas-345/ digitaltrip.hu: Mastech MAS-345 digital multimeter Windows GUI] ([https://github.com/libesz/MAS345_GUI github]) | |||
* [https://github.com/mschilli/device-mas345-perl github: device-mas345-perl] | |||
* [http://www.b-redemann.de/sp-DMM-auslesen.shtml b-redemann.de Auslesen von Messgeräten mit RS232 Interface über USB] | |||
* [http://freecode.com/projects/tmon tmon] (uses a MASTECH MAS345) | |||
Revision as of 01:30, 10 July 2012
The MASTECH MAS345 is a 3999 counts, CAT II handheld digital multimeter with RS232 connectivity.
It is also sold under the names Global Specialties Pro-70, Velleman DVM345DI, McVoice M-345pro, and Sinometer MAS345.
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)
- 14-stage binary counter/oscillator: ST 74HC4060 N00U732
- Precision Operational Amplifiers: Texas Instruments 12AL9JM 0P07CP
- ?: GC7555AP AA7057HS
- Opto Coupler: Sharp B B5 PC817
- Opto Coupler: 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
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, RTS low, DTR high
- 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
- Original English vendor manual (2008)
- elv.de: Download zu: Digital-Multimeter MAS-345 (68-04 59 88):
- German manual from ELV (2002)
- "DMM VIEW" software, version 2.0 (for Win98/NT/ME/2000/XP; supports MAS343, MAS344, MAS345, M9803R)
- cczwei-forum.de: C# software for reading DMM values
- Linux Magazin: E-Werke: Perl misst Stromverbrauch mit Multimeter
- mas-345/marsh: multimeter read and store
- digitaltrip.hu: Mastech MAS-345 digital multimeter Windows GUI (github)
- github: device-mas345-perl
- b-redemann.de Auslesen von Messgeräten mit RS232 Interface über USB
- tmon (uses a MASTECH MAS345)