atam862-8 ATMEL Corporation, atam862-8 Datasheet - Page 17

• Manufacturer Part Number: atam862-8
• Description: Atam862-8 Microcontroller With Uhf Ask/fsk Transmitter
• Manufacturer: ATMEL Corporation

16.3
16.3.1
4590G–4BMCU–06/07
Registers
Program Counter (PC)
Figure 16-2. RAM Map
The microcontroller has seven programmable registers and one condition code register (see
Figure
The program counter is a 12-bit register which contains the address of the next instruction to be
fetched from the EEPROM. Instructions currently being executed are decoded in the instruction
decoder to determine the internal micro-operations. For linear code (no calls or branches), the
program counter is incremented with every instruction cycle. If a branch-, call-, return-instruction
or an interrupt is executed, the program counter is loaded with a new address. The program
counter is also used with the table instruction to fetch 8-bit wide EEPROM constants.
Figure 16-3. Programming Mode l
16-3).
PC
SP
RP
X
Y
11
FCh
04h
00h
X
Y
RP
SP
Autosleep
TOS-1
(256 x 4-bit)
7
7
7
7
RAM
TOS
CCR
FFh
07h
03h
C
3
3
Expression
stack
Return
stack
--
Global
variables
Global
v
variables
B
0
I
0
0
0
0
0
0
0
0
Interrupt enable
Branch
Reserved
Carry / borrow
Program counter
Return stack pointer
Expression stack pointer
RAM address register (X)
RAM address register (Y)
Top of stack register
Condition code register
Expression stack
11
Return stack
3
TOS-1
TOS-2
4-bit
TOS
12-bit
0
ATAM862-8
SP
0
RP
17