Table of Contents
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Table of Contents
K80W Rev2.1, A RomWBW-capable Z80 SBC
Introduction
K80W is similar to K80. It is a 22MHz Z80 SBC with KIO (Z84C90) as the I/O device. It is designed to run RomWBW. The current version is rev 2.1 replacing the older K80W rev1.
Features
Z80 overclocked to 22MHz,
512KB Flash divided into 16 32KB banks,
512KB RAM divided into 16 32KB banks,
KIO, Z84C90, is the integrated I/O interface,
DS1302 Real Time Clock,
Compact Flash interface,
SD Card interface,
Designed for RomWBW,
Two 40-pin RC2014-compatible expansion slots,
100mm X 100mm, 2-layer PC board,
Design Files
RomWBW Configuration
The following modifications to RCZ80_K80W.ASM file is needed:
SDENABLE .SET TRUE ; SD: ENABLE SD CARD DISK DRIVER (SD.ASM)
SDMODE .SET SDMODE_PIO ; SD: DRIVER MODE: SDMODE_[JUHA|N8|CSIO|PPI|UART|DSD|MK4|SC|MT|PIO|Z80R|USR]
This is the resulting RCZ80_K80W.ASM
The I/O addresses for SDMODE_PIO is hardwired to $69. It is necessary to modify SD.ASM in HBIOS as follow:
SD_IOBASE .EQU $82 ; IO BASE ADDRESS FOR SD INTERFACE
SD_DDR .EQU $83 ; DATA DIRECTION REGISTER
This is the resulting ROM binary file for SST39SF040 that recognizes SD card connected to PIO: