Honeywell Mini-AT, User Manual, Page: 75 / 156

75
Page 75
Mini-AT User Guide
Flash Access Security Jumper
Mini-AT firmware (instrument operating instructions) is stored in flash memory Adding new features and capa-
bilities to the instrument is simply a matter of uploading a file containing a newer version of firmware through the
serial port connection. There are no EPROM chips to be removed or plugged into sockets.
Pins 5 & 6 of Jumper Block 24 (JB24) provides Flash Access Security. With a jumper across pins 5 & 6, the
user is permitted to upload newer firmware into Flash Memory. If there is no jumper across pin 5 & 6,
firmware upgrades will not be permitted. As a check, Item Code 268 can be read by Mini-AT Link to
determine what jumpers are installed on JB24. By default, the jumper is installed.
The serial connection for a firmware upgrade can be either the local serial port or via a modem. If the data is
transferred via the local serial port, item 126 may be set to 38.4 Kbaud to achieve the faster possible transfer
time. Conversely, if the transfer is via a modem, the transfer time will be noticeably longer for modems with
carrier speeds less than 38.4 Kbaud.
Serial Access Security Jumper
Pins 7 & 8 of Jumper Block 24 (JB24) provides Serial Access Security. If a jumper is across pins 7 & 8 when
a serial connection is established, TWO WAY serial communications is allowed regardless of the setting at
Item Code 139 (Serial Link Code). Also, with the jumper installed, the Instrument Baud Rate (item 126) and
Modem Baud Rate (item 272) are forced to operate at 9600 baud. When the jumper across pins 7 & 8 is
removed, the configuration of Item Codes 126, 139 and 272 are obeyed. By default, the jumper is removed.
JB24
(with jumper on pins 5 & 6)
1 3 5 7 9
2 4 6 8 10
JB24
(with jumper on pins 7 & 8)
1 3 5 7 9
2 4 6 8 10