XA-G39 Datasheet, PDF (12/42 Pages) NXP Semiconductors – XA 16-bit microcontroller family XA 16-bit microcontroller 32K FLASH/1K RAM, watchdog, 2 UARTs

Philips Semiconductors
XA 16-bit microcontroller family
32K Flash/1K RAM, watchdog, 2 UARTs
Preliminary data
XA-G39
V_CC
V_PP
V_DD SUPPLY OR +12V ±5%
FOR USE WITH WINISP OR FLASHMAGIC
RST
V_DD
TxD
XTAL2
RxD
XTAL1
V_SS
5V ±5%
TxD
RxD
V_SS
RS-232
TRANSCEIVER
MC145406, MAX232,
OR EQUIVALENT
2
3
5
FEMALE
DB-9
Figure 4. In-System Programming with a Minimum of Pins
SU01593
In-System Programming (ISP)
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
XA-G39 through the serial port. This firmware is provided by Philips
and embedded within each XA-G39 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_SS, V_DD, and V_PP (see
Figure 4). Only a small connector needs to be available to interface
your application to an external circuit in order to use this feature.
The V_PP supply should be adequately decoupled and V_PP not
allowed to exceed datasheet limits.
V_CC
5.0 V
5.0 V
V_PP
5.0 V
5.0 V
OSC FREQ
22 MHz
30 MHz
I_DD
75 mA typical
90 mA typical
ISP increases I_DD by less than 1mA.
Free ISP software is available on the Philips web site: “WinISP”
1. Direct your browser to the following page:
http://www.semiconductors.com/mcu/download/80C51/flash/
2. Download “WinISP.exe”
3. Execute WinISP.exe to install the software
Free ISP software is also available from the Embedded Systems
Academy: “FlashMagic”
1. Direct your browser to the following page:
http://www.esacademy.com/software/flashmagic/
2. Download Flashmagic
3. Execute “flashmagic.exe” to install the software
There is also an application note available that deals with In-System
Programming (AN716). At www.philipsmcu.com, search for “ISP”,
then select AN716 from the search results.
Using In-System Programming (ISP)
ISP mode is entered by holding PSEN low, asserting, un-asserting
RESET, then releasing PSEN. When ISP mode is entered, the
default loader first disables the watchdog timer to prevent a
watchdog reset from occurring during programming.
The ISP feature allows for a wide range of baud rates to be used in
the 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 (a lowercase f) be sent to
the XA-G39 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 specific Intel Hex-type records. Intel Hex records
consist of ASCII characters used to represent hexadecimal values
and are summarized below:
:NNAAAARRDD..DDCC<crlf>
In the Intel Hex record, the “NN” represents the number of data
bytes in the record. The XA-G39 will accept up to 16 (10H) data
bytes. The “AAAA” string represents the address of 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 1.
As a record is received by the XA-G39, the information in the record
is stored internally and a checksum calculation is performed. The
2002 Mar 13
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