P89C51RB2HBA NXP Semiconductors, P89C51RB2HBA Datasheet - Page 45

• Manufacturer Part Number: P89C51RB2HBA
• Manufacturer: NXP Semiconductors

Specifications of P89C51RB2HBA

• Cpu Family: 89C
• Device Core: 80C51
• Device Core Size: 8b
• Frequency (max): 33MHz
• Interface Type: UART
• Program Memory Type: Flash
• Program Memory Size: 16KB
• Total Internal Ram Size: 512Byte
• # I/os (max): 32
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• Instruction Set Architecture: CISC
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 44
• Package Type: PLCC
• Lead Free Status / Rohs Status: Not Compliant

Philips Semiconductors
In-System Programming (ISP)
The In-System Programming (ISP) is performed without removing
the microcontroller from the system. The In-System Programming
(ISP) facility consists of a series of internal hardware resources
coupled with internal firmware to facilitate remote programming of
the P89C51RB2/RC2/RD2Hxx through the serial port. This firmware
is provided by Philips and embedded within each
P89C51RB2/RC2/RD2Hxx device.
The Philips In-System Programming (ISP) facility has made in-circuit
programming in an embedded application possible with a minimum
of additional expense in components and circuit board area.
The ISP function uses five pins: TxD, RxD, V
Figure 44). Only a small connector needs to be available to interface
your application to an external circuit in order to use this feature.
The V
allowed to exceed datasheet limits.
Using the In-System Programming (ISP)
The ISP feature allows for a wide range of baud rates to be used in
your application, independent of the oscillator frequency. It is also
adaptable to a wide range of oscillator frequencies. This is
accomplished by measuring the bit-time of a single bit in a received
character. This information is then used to program the baud rate in
terms of timer counts based on the oscillator frequency. The ISP
feature requires that an initial character (an uppercase U) be sent to
the P89C51RB2/RC2/RD2Hxx to establish the baud rate. The ISP
firmware provides auto-echo of received characters.
Once baud rate initialization has been performed, the ISP firmware
will only accept Intel Hex-type records. Intel Hex records consist of
ASCII characters used to represent hexadecimal values and are
summarized below:
In the Intel Hex record, the “NN” represents the number of data
bytes in the record. The P89C51RB2/RC2/RD2Hxx will accept up to
16 (10H) data bytes. The “AAAA” string represents the address of
2002 May 24
80C51 8-bit Flash microcontroller family
16KB/32KB/64KB ISP/IAP Flash with 512B/512B/1KB RAM
:NNAAAARRDD..DDCC<crlf>
PP
supply should be adequately decoupled and V
Figure 44. In-System Programming with a Minimum of Pins
SS
, V
CC
V
CC
, and V
PP
not
PP
RST
XTAL2
XTAL1
V
SS
(see
89C51RC2Hxx
89C51RD2Hxx
89C51RB2Hxx
42
the first byte in the record. If there are zero bytes in the record, this
field is often set to 0000. The “RR” string indicates the record type.
A record type of “00” is a data record. A record type of “01” indicates
the end-of-file mark. In this application, additional record types will
be added to indicate either commands or data for the ISP facility.
The maximum number of data bytes in a record is limited to 16
(decimal). ISP commands are summarized in Table 7.
As a record is received by the P89C51RB2/RC2/RD2Hxx, the
information in the record is stored internally and a checksum
calculation is performed. The operation indicated by the record type
is not performed until the entire record has been received. Should
an error occur in the checksum, the P89C51RB2/RC2/RD2Hxx will
send an “X” out the serial port indicating a checksum error. If the
checksum calculation is found to match the checksum in the record,
then the command will be executed. In most cases, successful
reception of the record will be indicated by transmitting a “.”
character out the serial port (displaying the contents of the internal
program memory is an exception).
In the case of a Data Record (record type 00), an additional check is
made. A “.” character will NOT be sent unless the record checksum
matched the calculated checksum and all of the bytes in the record
were successfully programmed. For a data record, an “X” indicates
that the checksum failed to match, and an “R” character indicates
that one of the bytes did not properly program. It is necessary to
send a type 02 record (specify oscillator frequency) to the
P89C51RB2/RC2/RD2Hxx before programming data.
The ISP facility was designed to that specific crystal frequencies
were not required in order to generate baud rates or time the
programming pulses. The user thus needs to provide the
P89C51RB2/RC2/RD2Hxx with information required to generate the
proper timing. Record type 02 is provided for this purpose.
WinISP, a software utility to implement ISP programming with a PC,
is available on Philips Semiconductors’ website. In addition, at the
website is a listing of third party commercially available serial and
parallel programmers.
P2.7
P2.6
V
TxD
RxD
V
CC
PP
P89C51RB2/P89C51RC2/
SU01299
+5 V (+12 V tolerant)
+5 V
TxD
RxD
V
“1”
“1”
SS
P89C51RD2Hxx
Product data