User`s manual

BL1600108 s EEPROM
EEPROM Parameters
The onboard EEPROM (electrically erasable, programmable, read-only
memory) is used to store the constants and parameters listed in Table F-1.
The five bytes presently in use determine the operation of the BL1600
board when it starts up.
The EEPROM has 512 bytes. The upper 256 bytes can be written to only
when pins 19 and 21 on header J1 are connected. Connect pins 17 and 19
on header J1 to write-protect the EEPROM.
Baud Rate
When the EEPROM is first initialized, the baud rate is set to 57,600 bps.
The next section outlines the procedure to change these parameters.
Startup Mode
In programming mode, the board initializes Serial Port 0 for Dynamic C.
When set for run mode, the board attempts to execute a user-written
program stored in battery-backed RAM or in EPROM.
The baud rate code determines the serial communication rate at which the
BL1600 attempts to communicate with the PC and Dynamic C.
Table F-1. BL1600 EEPROM Assignments
Address Definition
0
Startup Mode — if 1, enter program mode; if 8, execute
loaded program at startup.
1
Programming baud rate in multiples of 1200 bps. The fac-
tory default is 48, meaning 57,600 bps. This location ap-
plies only if J1 pins 1–2 are not connected and J1 pins 3–4
are connected.
0x100
Unit “serial number” in BCD time and date with the fol-
lowing format: second, minutes, hours, day, month, and
year.
0x108
Microprocessor clock speed in multiples of 1200 Hz (16
bits). (This value is 7680 for a 9.216 MHz clock speed.)
0x16C
Long coefficient relating speed of microprocessor clock
relative to speed of real-time clock. Nominal value is
107,374,182, which is 1/40 of a second microprocessor
clock time on the scale where 2
32
is 1 second. This requires
4 bytes of EEPROM, stored least byte first.