Nokia 3105 Servicehandbuch
CCS Technical Documentation
Troubleshooting — BB
RH-48
Issue 1 11/2003
© 2003 Nokia Corporation Confidential
Page 17
flash-programming mode, the MCU only waits for a specified time to get input data from
the flash prommer. If the timer expires without any data being received, the MCU will
continue the boot sequence. The MBUS signal from UEM to the external connection is
used as clock during flash programming. This means that flash-programming clock is
supplied to UPP on the MBUSRX signal.
the flash prommer. If the timer expires without any data being received, the MCU will
continue the boot sequence. The MBUS signal from UEM to the external connection is
used as clock during flash programming. This means that flash-programming clock is
supplied to UPP on the MBUSRX signal.
The flash prommer indicates the UEM that flash programming/reprogramming by writing
an 8-bit password to the UEM. The data is transmitted on the FBUSRX line and the UEM
clocks the data on the FBUSRX line into a shift register. When the 8 bits have been
shifted in the register, the flash prommer generates a falling edge on the BSI line. This
loads the shift register content in the UEM into a compare register. If the 8 bits in the
compare registers matches with the default value preset in the UEM, the flash prommer
shall pull the MBUS signal to UEM low in order to indicate to the MCU that the flash
prommer is connected. The UEM reset state machine performs a reset to the system,
PURX low for 20 ms. The UEM flash programming mode is valid until MCU sets a bit in
the UEM register that indicates the end of flash programming. Setting this bit also clears
the compare register in the UEM previously loaded at the falling edge of the BSI signal.
During the flash programming mode the UEM watchdogs are disabled. Setting the bit
indicating end of flash programming enables and resets the UEM watchdog timer to its
default value. Clearing the flash programming bit also causes the UEM to generate a
reset to the UPP.
an 8-bit password to the UEM. The data is transmitted on the FBUSRX line and the UEM
clocks the data on the FBUSRX line into a shift register. When the 8 bits have been
shifted in the register, the flash prommer generates a falling edge on the BSI line. This
loads the shift register content in the UEM into a compare register. If the 8 bits in the
compare registers matches with the default value preset in the UEM, the flash prommer
shall pull the MBUS signal to UEM low in order to indicate to the MCU that the flash
prommer is connected. The UEM reset state machine performs a reset to the system,
PURX low for 20 ms. The UEM flash programming mode is valid until MCU sets a bit in
the UEM register that indicates the end of flash programming. Setting this bit also clears
the compare register in the UEM previously loaded at the falling edge of the BSI signal.
During the flash programming mode the UEM watchdogs are disabled. Setting the bit
indicating end of flash programming enables and resets the UEM watchdog timer to its
default value. Clearing the flash programming bit also causes the UEM to generate a
reset to the UPP.
The BSI signal is used to load the value into the compare register. In order to avoid spuri-
ous loading of the register, the BSI signal will be gated during UEM master reset and dur-
ing power on when PURX is active. The BSI signal should not change state during normal
operation unless the battery is extracted; in this case, the BSI signal will be pulled high,
note a falling edge is required to load the compare register.
ous loading of the register, the BSI signal will be gated during UEM master reset and dur-
ing power on when PURX is active. The BSI signal should not change state during normal
operation unless the battery is extracted; in this case, the BSI signal will be pulled high,
note a falling edge is required to load the compare register.
Flashing
• Flash programming is done through VPP, FBUSTX, FBUSRX, MBUS, and BSI signals.
• When phone has entered the flash programming mode, the prommer indicates to UEM
that flash programming will take place by writing 8-bit password to UEM. The prom-
mer sets BSI to “1” and then uses FBUSRX for writing and MBUS for clocking. After
that, BSI is set back to “0”.
mer sets BSI to “1” and then uses FBUSRX for writing and MBUS for clocking. After
that, BSI is set back to “0”.
• MCU indicates to prommer that it has been noticed, by using the FBUSTX signal. After
this, it reports UPP type ID and is ready to receive secondary boot code to its internal
SRAM.
SRAM.