Table of Contents
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Table of Contents
K80W Rev1, A RomWBW-capable Z80 SBC
Introduction
Note, K80W rev1 is superceded by K80W rev2.1
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
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,
Designed for RomWBW
Two 40-pin RC2014-compatible expansion slots,
100mm X 100mm, 2-layer PC board,
Design Files
Software
Adding SD to K80W
PB0 to MOSI,
PB7 to MISO,
PB3 to CS and
PB4 to CLK
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 that recognizes SD card connected to PIO: