UPD784035YGC NEC, UPD784035YGC Datasheet - Page 49

• Manufacturer Part Number: UPD784035YGC
• Description: 16-/8-BIT SINGLE-CHIP MICROCONTROLLERS
• Manufacturer: NEC

(bits 8 through 11
of temporary register)
8.3
is selected by hardware. Context switching is a function that branches execution to a vector address stored in advance
in the register bank, and to stack the current contents of the program counter (PC) and program status word (PSW)
to the register bank.
8.4
CPU. A macro service controller accesses the memory and SFR in the same transfer cycle and directly transfers
data without loading it.
speeds.
When an interrupt request is generated or when the BRKCS instruction is executed, a predetermined register bank
The branch address is in a range of 0 to FFFFH.
This function is to transfer data between memory and a special function register (SFR) without intervention by the
Because this function does not save or restore the status of the CPU, or load data, data can be transferred at high
PC19-16
<1> Save
<2> Save
Context Switching
Macro Service
0000B
PSW
<7> Transfer
Temporary register
Figure 8-1. Context Switching Operation When Interrupt Request Is Generated
PC15-0
<6> Exchange
<5> Save
CPU
Internal bus
W
V
U
T
Figure 8-2. Macro Service
Memory
Register bank n (n = 0 to 7)
PD784035Y, 784036Y, 784037Y, 784038Y
R5
R7
A
B
D
H
VP
UP
Read
Write
R4
R6
X
C
E
L
Macro service
<3> Switching of register bank
<4> RSS
controller
(RBS0 to RBS2
IE
n
n
Read
Write
Register bank n
n)
(0 to 7)
SFR
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