Commit Graph

4 Commits

Author SHA1 Message Date
Gregory Nutt
8c00e43c1a arch/z80/src/ez80: Fix eZ80F92 Interrupt Controller
The eZ80F92 interrupt controller is very different from the eZ80F91.  The eZ80F91 has:

1. Four byte interrupt vectors
2. The vector base address register is 16-bit so the vector table can lie in RAM

Whereas the eZ80F92 has:

1. Two byte interrupt vectors
2. An 8-bit vector base address

This means that the vectors must lie in the first 16-bits of FLASH and there must be a "trampoline" to get to interrupt handlers outside of the first 64-Kb of FLASH.
2020-02-28 19:45:28 +00:00
Gregory Nutt
161104c76a eZ80/z20x: Correct uninitialized stack memory
arch/z80/src/ez80/Toolchain.defs:  Correct some CFLAGS when optimization suppressed.

arch/z80/src/ez80/Kconfig arch/z80/src/ez80/ez80_emac.c:  Remove configuration option for selecting EMAC RAM address.  This is duplicated and possibly conflicting.  The correct address for the RAM is provided in the linker command file.  The RAM should be configured once and using this single definitions.

arch/z80/src/ez80/ez80_startup.asm and arch/z80/src/ez80/ez80f9*_init.asm.  Move RAM and FLAH intialization out of MCU-specific logic to common start-up logic.  We cannot call any functions until SRAM is initialized and the stack is properly initialized because the return address is stored on the stack.  Use internal SRAM for the IDLE stack to avoid the chicken'n'egg problem.

boards/z80/ez80/z20x/configs/sdboot/sdboot.zdsproj:  Discuss build environments.
2020-02-27 22:53:27 +01:00
Gregory Nutt
a9610e16bd boards/z80/ez80/z20x: Update CFLAGS and linker scripts.
arch/z80/src/ez80/Toolchain.defs:  Update some CFLAGS to match CFLAGS from ZDS-II IDE.  Apparently, we must say that the CPU is an eZ80F91 event when compiler for eZ80F92.
boards/z80/ez80/z20x:  Update linker scripts.
2020-02-26 21:12:01 +01:00
Gregory Nutt
5a3e8874bc boards/z80/ez80/z20x: Initial port to z20x board.
The Z20X is a simple expandable DIY computing system, built around the eZ80 microprocessor.  Reference: https://z20x.computer
2020-02-21 15:20:36 +01:00