NXP Flash MCU to Atmel Flash MCU Cross Reference. 07/01/ 86KB. NXP Flash MCU to Atmel Flash MCU Devices, Non-Direct Replacements. 07/01/ The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard 80C51 instruction set and. 89C55 datasheet, 89C55 circuit, 89C55 data sheet: ATMEL – 8-Bit Microcontroller with 20K Bytes Flash,alldatasheet, datasheet, Datasheet search site for.
|Genre:||Health and Food|
|Published (Last):||3 May 2013|
|PDF File Size:||8.54 Mb|
|ePub File Size:||1.53 Mb|
|Price:||Free* [*Free Regsitration Required]|
For example, the following indirect addressing instruction, where R0 contains 0A0H, accesses the data byte at address 0A0H, rather than P2 whose address is 0A0H.
Instructions that use direct addressing access SFR space. XTAL1 Input to the inverting oscillator amplifier and input to the internal clock operating circuit. When 1s are written to 89c555 3 pins, atmeel are pulled high by the internal pullups and can be used as inputs. T0 timer 0 external input. T1 timer 1 external input.
At89c55-24jc Atmel IC Microcontroller 8-bit 44 Pin PLCC MCU 89c55-24jc
When 1s are written to port 0 pins, the pins can be used as high- impedance inputs. The AT89C55 provides the following standard features: The Power Down Mode saves the RAM con- tents but freezes the oscillator, disabling all other chip func- tions until the next hardware reset.
XTAL2 Output from the inverting oscillator amplifier. As inputs, Port 3 pins that are externally being pulled low will source current I.
As an output port, each pin can sink eight TTL inputs. Port 3 also serves the functions of various special features of the AT89C55, as shown in the following table. INT1 external interrupt 1. RXD serial input port.
Search field Part name Part description. INT0 external interrupt 0. In addition, the AT89C55 is designed with static logic for operation down to zero frequency and sup- ports two software selectable power saving modes.
Port 1 also receives the low-order address bytes during Flash programming and verification. RD external data memory read strobe. External pullups are required during program verifica- tion. Port 0 also receives the code bytes during Flash program- ming and outputs the code bytes during program verifica- tion.
89C55 Datasheet(PDF) – ATMEL Corporation
Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode. Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset. Read accesses to these addresses will in general return random data, and write accesses will have an indetermi- nate atnel.
When 1s are written to Port 2 pins, they are pulled high by the internal pullups and can be used as inputs. Note that not all of the addresses are occupied, and unoc- cupied addresses may not be implemented on the atmwl. The device is manu- factured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard 80C51 instruction set and pinout. In that case, the reset or inactive values of the new bits will always be 0. WR external data memory write strobe.
A high on this pin for two machine cycles while the oscillator is running resets the device. Three-Level Program Memory Lock.
This pin also receives the volt programming enable volt- age V. Port 3 also receives the highest-order address bit and some control signals for Flash programming and verifica- tion. Two priorities can be set for each of the six interrupt atmeel in the IP register.
The upper bytes occupy a parallel address space to the Special Function Registers. Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use bit addresses MOVX DPTR. User software should not write 1s to these unlisted loca- tions, since they may be used in future products to invoke new features.
In this application, Port 2 uses strong internal pul- lups when emitting 1s. Note, however, that one ALE pulse is skipped during each access to external data mem- ory.
In this mode, P0 has internal pul- lups. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile 89d55 programmer. When 1s are written to Port 1 pins, they are pulled high by the internal pullups and can be used as inputs. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C55 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications.
The low-voltage option saves power and operates with a 2. As inputs, Port 1 pins that are externally being pulled low will source current I.
As inputs, Port 2 pins that are externally being pulled low will source current I. TXD serial output port. Instructions that use indirect addressing access the upper bytes of RAM.
Interrupt Registers The individual interrupt atmwl bits are in the IE register. EA should be strapped to V. Note that stack operations are examples of 89f55 addressing, so the upper bytes of data RAM are avail- able as stack space.
Otherwise, the pin is weakly pulled high.