Download 1 The Kernel

defined this macro in variant.inc – it initializes the interrupt controller there (interrupt
control mode 2).
In macro hal_memc_init we initialise MCU2357 bus- and memory controller and
general purpose I/O.
We can keep a lot of this macro but we have to change the registers and their values in
init_regs. For MCU2357 board the register initialisation values look like this (we use
the symbolic register names von module register include files of H8S/2357 variant):
...
init_regs:
INIT_REGS_DATA(CYGARC_ABWCR, 0xFF)
INIT_REGS_DATA(CYGARC_ASTCR, 0xFF)
INIT_REGS_DATA(CYGARC_BCRH,
0x00)
INIT_REGS_DATA(CYGARC_BCRL,
0x1C)
INIT_REGS_DATA(CYGARC_WCRH,
0xFF)
INIT_REGS_DATA(CYGARC_WCRL,
0xFF)
INIT_REGS_DATA(CYGARC_MCR,
0x00)
INIT_REGS_DATA(CYGARC_DRAMCR, 0x00)
INIT_REGS_DATA(CYGARC_RTCOR, 0x00)
INIT_REGS_DATA(CYGARC_P6DDR, 0x00)
INIT_REGS_DATA(CYGARC_PADDR, 0x00)
INIT_REGS_DATA(CYGARC_PBDDR, 0xFF)
INIT_REGS_DATA(CYGARC_PCDDR, 0xFF)
INIT_REGS_DATA(CYGARC_PFDDR, 0x80)
INIT_REGS_DATA(CYGARC_MSTPCRL,0x00)
.word
0
...
5.5.4 Platform source files
5.5.4.1 plf_misc.c
This file contains miscellaneous platform specific functions provided by HAL. The first
function we need to modify a little bit is hal_clock_initialize. We use TPU channel
5 like EDOSK-2674 board but we need a clock divider of 4 (EDOSK-2674 uses a clock
divider of 16) in order to get a 100 Hz frequency for eCos real-time clock. We have to
change only one single line within this function:
...
// initialize 16 bit timer - first we select timer counter clock and
// counter clearing source TGR
// Clock prescaler is 4 (clock/4) and TCNT is clear at compare match A
//
HAL_WRITE_UINT8(CYGARC_TCR5, CYGARC_TCR_CLR_CMA | CYGARC_TCR_TPSC_4);
...
Now we only need to remove the function cyg_plf_memory_segment, because the
MCU2357 board contains only one memory segment, and we are finished with this file.
Porting Guide
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