User Guide

PAMS
Technical Documentation
NSE–8/9
System Module
Page 2– 56
Issue 1 07/99
MAD FLASH down loading power up
The FLASH down loading power up procedure is similar to that of DCT2.
The only difference is that instead of external RAM the internal API RAM
may be used to store the FLASH down loading program (if the down
loading program fits into the API RAM it is stored there, if not then it is
stored to external RAM). The procedure is described below.
0. INITIAL CONDITIONS: POWER UP RESET (PURX) IS ACTIVE
– MAD2PR1 is in RESET mode
1. POWER UP RESET (PURX) RELEASED:
1.1 MAD2PR1 releases the MCU reset (MCUResetX) and the external
system reset (ExtSysReset)
2. MCU BOOTS UP FROM SYSTEM LOGIC BOOT ROM:
2.1 MCU starts to read the boot code from system logic boot ROM
2.2 MCU checks if the FLASH prommer is connected (by studying the
status of serial synchronous clock input at MBUS line)
2.3 If prommer connected (MBUS low) then continue this procedure,else
go to normal MAD2PR1 power up procedure
2.4 MAD2PR1 acknowledges the presence of the prommer by setting the
FBUS–TX line low
2.5 FLASH prommer sends the first two bytes of data to MCU which
indicate the length of the secondary boot code
2.6 MCU acknowledges the reception of the secondary boot code length
by setting the FBUS–TX line high
2.7 FLASH prommer loads the secondary boot code to API RAM using the
serial syn chronous interface (PUP USART, FBUS–RX as data line and
MBUS line as clock)
2.8 MCU acknowledges the reception of the secondary boot code by
setting the FBUS–TX line low
3. MCU CONTINUES BOOTING FROM API BOOT CODE
3.1 MCU disables the system logic boot ROM
3.2 MCU starts to test the external RAM and sets the FBUS TX line high
3.3 If external RAM test is passed then MCU sets the FBUS TX line low, if
failed the booting is interrupted
3.4 MCU reads the system configuration data from FLASH memory (two
bytes)
3.5 MCU sends (parts of) the system configuration data to FLASH
prommer
3.6 MCU sets the FBUS TX line high to indicate that it is ready to receive
the FLASH programming SW (to either API RAM or external RAM)
3.7 FLASH prommer loads the FLASH programming SW to the RAM
4. MCU SWITCHES TO RUN THE CODE FROM THE FLASH
PROGRAMMING SW
4.1 MCU initializes itself according to the FLASH programming SW