gc80c520a CORERIVER Semiconductor, gc80c520a Datasheet - Page 33
gc80c520a
Manufacturer Part Number
gc80c520a
Description
Midas1.0 Family Mask Rom/eprom/romless 8-bit Turbo Microcontrollers
Manufacturer
CORERIVER Semiconductor
Datasheet
1.GC80C520A.pdf
(187 pages)
- Current page: 33 of 187
- Download datasheet (2Mb)
It is not obvious that the last three instructions in this list are read-modify-write instructions, but they are.
They read the port byte, all 8 bits, modify the addressed bit, then write the new byte back to the latch.
The reason that read-modify-write instructions are directed to the latch rather than the pin is to avoid a
possible misinterpretation of the voltage level at the pin. For example, a port bit might be used to drive the
base of transistor. When logic 1 is written to the bit, the transistor is turned on. If the CPU the reads the
same port bit at the pin rather than the latch, it will read the base voltage of the transistor and interpret it
as logic 0. Reading the latch rather than the pin will return the correct value of logic 1.
6.2.1.10 Alternate Functions
All the port pins are multifunctional. They also serve the alternate functions specified below. The alternate
functions can only be activated if the corresponding bit latch in the port SFR contains logic 1. Otherwise
the port pin is stuck at 0. The alternate functions are activated respectively. They will be activated or
inactivated according to the application. More information about each alternate function will be provided
later.
MiDAS1.0 Family
Instruction
MOV PX.Y, C
SETB PX.Y
CLR PX.Y
DJNZ
ANL
ORL
DEC
XRL
JBC
CPL
INC
Table 6-4 Read-Modify-Write Instructions
Page 33 of 187
Description
Logical AND
Logical OR
Logical Exclusive OR (XOR)
Branch if bit is set then clear bit
Complement bit
Increment
Decrement
Decrement and branch if not zero
Move the carry bit to bit Y of Port X
Clear bit Y of Port X
Set bit Y of Port X
Related parts for gc80c520a
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Coreriver Semiconductor
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
CRITOUCHCORE3.0-MLF32 PSOC(TOUCHCORE30-
Manufacturer:
Coreriver Semiconductor Co.
Part Number:
Description:
Digital-type / Capacitive Touch Sensor Engine
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
Flash / Isp / Iap 8-bit Turbo Microcontrollers
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
Eprom / Rom / Romless Based 8-bit Turbo Microcontrollers
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
Eprom/rom 8-bit Turbo Microcontrollers
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
Flash / Isp / Iap 8-bit Turbo Microcontrollers
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
4-bit Microcontrollers With Reduced 8051 Architecture With Reduced 8051 Architecture
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
4-bit Microcontrollers With Reduced 8051 Architecture
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
4-bit Microcontrollers With Reduced 8051 Architecture
Manufacturer:
CORERIVER Semiconductor
Datasheet:
Part Number:
Description:
Digital-type / Capacitive Touch Sensor Engine
Manufacturer:
CORERIVER Semiconductor
Datasheet: