waltje / co2-pocket-sbc-2.5 Goto Github PK

C02 Pocket SBC 2.5 - prototype

Hardware:

Note that there is not an existing PCB layout as of yet.

The schematics are done with ExpressPCB.

The prototype system is built on a pair of slightly modified PCBs for the C02 Pocket SBC 2 and the CF-Card/RTC adapter (more like cobbled together).

A hand-wired Adapters was made for the SC28L92 DUART A 32-pin DIP socket and a few wires were used to add the 128KB SRAM

A small breakout PCB and flat cable have been wired to the bottom of the CF Card/RTC adapter to attach the Microdrive via it’s small 35-pin FPC cable.

WinCUPL is used for the two PLDs

ATF22LV10C: PLD code is slightly changed for the memory mapping of SRAM and EEPROM only

• 56KB SRAM and 8KB EEPROM

ATF16LV8C PLD code for the CF Card/RTC adapter is standard

Software:

DOS/65 Core OS contains Version 3.20.

Utilities folder contains:

• Version 2.x Source files for Utilities (can be assembled on C02 Pocket)

• V3 Utils Folder contains:

• Assembler, MakeCOM, Submit, Super Directory, User Copy and Xmodem utilities for WDC Tools

• Standard Source files are provided with DOS/65 V3.0

/Software/ROM Code directory contains:

• BIOS and Monitor for C02 Pocket SBC 2.5 Prototype
• Microdrive/Realtime Clock utility

WDC Tools is used to build:

• all of the ROM code (BIOS, Monitor) for the SBC
• the Microdrive/RTC utility
• DOS/65 Version 3.20
• V3 Utils Folder; SD, ASM, Makecom, Submit, Ucopy, Xmodem

CO2 Monitor provides Xmodem Upload/Download capability via the Console port.

• The Download will automagically sense and process the S19 records created by WDC Tools.

Once you have the hardware assembled and the ROM code loaded (working system).

• you can use Xmodem download from CO2 Monitor to: load DOS/65 RAM Image load MD/RTC Utility

Use the utility (g 800 ) to put the DOS image on the Microdrive

• S to perform System Load
• 131072 offset for the LBA number to start at
• B800 for the RAM start address
• 20 for the block count
• Y to write it to disk.

Use Ctrl-B from Monitor to load and start DOS/65

• use go 57344 to return to Monitor

You can download the WDC created utilities via the CO2 Monitor, then invoke DOS/65 and use the Save command to move them to disk as follows:

Save # name.com, where # is the number of 256-byte pages to save and name.com is the utility name you want it saved as.

Once you have the main DOS system and the base utilities loaded, you can use Xmodem to download the main utilities. There is a makeutil.sub file that will build the entire set on the CO2 Pocket SBC. It assumes the source files are located on drive B:

If you prefer to use a different drive, be sure to edit the .sub file.

Have Fun!