Rainbow Electronics ATmega163L - Manual (Page 124)

ATmega163(L)
124
• CKSEL3..0 select the clock source and the start-up delay after reset, according to Table 1 on page 5 and Table 5 on
page 22. Default value is ‘0010’ (Internal RC Oscillator).
The status of the Fuse bits is not affected by Chip Erase. Note that the Fuse bits are locked if lock bit1 (LB1) is pro-
grammed. Program the Fuse bits before programming the Lock bits.
Signature Bytes
All Atmel microcontrollers have a three-byte signature code which identifies the device. This code can be read in both serial
and parallel mode. The three bytes reside in a separate address space.
The ATmega163 the signature bytes are:
1. $000: $1E (indicates manufactured by Atmel)
2. $001: $94 (indicates 16KB Flash memory)
3. $002: $02 (indicates ATmega163 device when $001 is $94)
Calibration Byte
The ATmega163 has a one byte calibration value for the internal RC Oscillator. This byte resides in the high byte of
address $000 in the signature address space. To make use of this byte, it should be read from this location and written into
the normal Flash program memory by the external programmer.
Parallel Programming
This section describes how to parallel program and verify Flash Program memory, EEPROM Data memory + Program And
Data Memory Lock bits and Fuse bits in the ATmega163. Pulses are assumed to be at least 500ns unless otherwise noted.
Signal Names
In this section, some pins of the ATmega163 are referenced by signal names describing their functionality during parallel
programming, see Figure 81 and Table 55. Pins not described in the following table are referenced by pin names.
The XA1/XA0 pins determine the action executed when the XTAL1 pin is given a positive pulse. The bit coding are shown
in Table 56.
When pulsing WR or OE, the command loaded determines the action executed. The Command is a byte where the differ-
ent bits are assigned functions as shown in Table 57.