Remote Technologies RPC-320 User Manual
Page 20
RAM MEMORY
SECTION 5
Page 5-1 RPC -320
Figure 5-1 RAM and W1 ju mper location
INTRODUCTION
32K, 128K, or 512K of RAM may be battery backed on
the RPC-320. RA M size can be changed at any time.
RAM is in socket U5.
RAM is backed up when a DS1216DM is installed.
Battery life depends upon RAM size, its power
c o ns u m pt io n , a mb ie n t t em p e r at ur e , a nd a m ou n t o f ti m e
the board is operating. Gener ally, a battery life of about
3 to 5 y ea rs is e xp ec ted . Op er ati ng the bo ar d a t 50 °C
reduces battery life by 1/2.
The DS1216DM is also a real time clock. Thus, DATE
and TIM E function s and com mands a re availa ble when it
is installed. See Chapter 7 for more inform ation.
This chapter discusses changing RAM, saving and
retrieving variables, r unning assembly language
program s, and battery condition. F igure 5-1 shows the
location of U3 and jumper W1.
Increasing RAM size does not necessarily increase the
program size RPBASIC-52 can handle. Maximum
program and variable size is 60K. Additional RAM does
increase the amount of space available for PEEK and
POKE storage.
CHANGING MEMORY
Different types of memory can be installed at any time.
RPC-320 models come with either 32K or 128K of RAM
installed. Maximum is 512K.
To change a mem ory chip, you need to rem ove the
original chip, install the new one, and set jumper W 1.
To install a new memory chip:
1.
Turn off power to the RPC-320.
2.
Remove the mem ory chip from U 5.
3.
Orient the chip so pin 1 is towards the inside.
If installing a 32K RAM , place the chip at the
bottom of the socket (m emor y chip pin 1 goe s into
socket pin 3). The top two socket pins in each row
are empty.
If installing a 128K or 512K, install the chip into the
socket.
4.
Check and change , as n ecessar y, jum per W 1 to
conform to the new mem ory.
RAM size
J um p er W 1
32K
[1-2]
128K
[1-2]
512K
[2-3]
BATTERY BACKUP
An optional battery backup module may be installed.
Principal is the same as installing a RAM chip.
WARNING:
An additional modification must be performed to the
DS1216DM module when a 512K RAM is installed.
Contact Rem ote Processing fo r details.
To install a module:
1.
Remove the RAM IC in U5.
2.
Install the DS1216DM in U5.
3.
Re-install the RAM chip into the top of the module.
Checking the battery
Battery voltage is approximately 3.0 volts, measured
between pin 16 (ground) and 30 (128K RAM ), 14 and 28
(32K RA M), or 16 and 32 (512K R AM ) on the IC itself
(not the circuit side of the board). Be sure to pow er up
the RPC -320 once to a ctivate the batter y backup cir cuit
in the module.