RIM 1802G, Руководство интегратора

Страница: 58 / 76

Chapter 6: Interface specification
58 RIM OEM Radio Modem for GSM/GPRS Wireless Networks
Resetting the radio
RIM recommends that you incorporate a method to remove power from pins 7 and 8 on the radio
modem during the development and prototype phase. This enables the device to perform a hard
reset of the radio modem, which can be useful in some debugging testing situations.
Loading firmware (optional)
RIM firmware controls the operation of the radio modem. RIM is committed to the quality of its
firmware, and might periodically make improvements or optimizations to it. The radio modem is
designed so that loading revised firmware is not required; two RIM GPRS radio modems with
different firmware revisions are always able to communicate with each other, and with the same
fixed servers, through the wireless network. Nevertheless, you might choose to design your
application in such a way that allows the RIM firmware to be updated after your product is
deployed in the field.
Because of its large size, firmware cannot be updated wirelessly. If you decide to implement the
ability to update the firmware after the radio modem is deployed, RIM can provide a command-line
programming utility that loads firmware into the radio modem. If your device is not based on a
command prompt, the programming utility must reside on a computer that is connected through its
COM port to the radio modem’s RX and TX lines. This means that the RX and TX lines are brought
out to an external connector, and a switch is required to select whether the radio modem is
connected to your processor or to the external programming computer. Other lines that are required
during reprogramming are DTR (must be asserted low) and GND.
This external serial port can also be useful for FCC certification testing, and RIM highly
recommends that this be incorporated into at least one device that is designated for testing
purposes.