Maiden Rock Communications LLC MRC565-47-50 ユーザーズマニュアル

OPERATIONS

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MRC-565 Packet Data Radio Operations & Maintenance

To now replay the data, determine the current pointer and note the date and time of the pointer
reading. Each site uses about 50 words of CR10X final storage per hour, therefore determine
how many hours you want to move the pointer back. Multiply by 50 and subtract the result from
the current point. Send the new pointer to the remote with the CR10X,SETPTR,nnnnnn
command. The remote will send back the new pointer setting:

11/27/02 14:42:41 Command response received from 00500
#cr10x,setptr,2300 A1 L+2300 C0884
# 11/27/02 14:42:33 Completed

# 11/27/02 14:42:31
# R+292750. F+2453. V5 A1 L+2454. E00 00 32 M0256 B+3.1027 C2991
# MRC-565A DPTR:291200 331 13:33, CR10X Start:331 10:04 End:331 13:46

In this example, the pointer was set back from 292750 to 291200- about 31 hours.

NOTE 1

2043 will report four groups hourly and will use about 70 words per hour.

NOTE 2

If the pointer calculation goes negative the pointer has wrapped around. Add the

maximum pointer value to the negative pointer (“F”?) to determine the proper value.

5.8 CR1000 Data Logger

The MRC-565 Packet Data Radio (hereafter called the radio) can be used with the Campbell
Scientific CR1000 data logger to transmit data from a remote site to a destination in a Meteor
Burst (MB) or Line-Of-Sight (LOS) network. Because of the unique timing of a MB system, the
radios do not provide a real-time connection between a CR1000 and a PC running a data
collection program as a pair of dedicated phone modems would. The connection is a packet
store-and-forward type instead.

Each CR1000 table data array recorded in the final storage is treated as a data logger packet by
the radio. Packets are acquired by the radio from the CR1000, and delivered through the MB
network to another relay radio or master station. The packets are then "printed" on one of the RS-
232 ports, or Ethernet port at the destination unit in a format that is compatible with all the other
supported data loggers.

In this type of system, the central data system does not "poll" each remote for its data. Instead,
each remote radio gets the data from the locally attached CR1000 using an internal data
acquisition schedule and CR1000 driver software module, then routes it to a particular
destination. The radio’s driver module uses the Campbell Scientific PakBus Network Layer and
SerPkt serial port protocols to read the data from the CR1000 Tables. Data is reformatted into the
SDATA and MBNET standard format for transmission. It is the responsibility of the central data
system to store and process the data as it arrives from each remote site.