This configuration is specifically for the SC503, Z180 Processor card.
The latest release of this Firmware is detailed in the table below.
| Name | Wayne Warthen’s RomWBW |
| Build name | Small Computer SC503 |
| Build date | 2025-05-21 |
| Platform | SCZ180 |
| Configuration | sc503_std |
| Version | v3.5.1 |
| Download ROM image | RomWBW-SCZ180_sc503_std v3.5.1 Dated 2025-05-21 |
| Suggested ROM label | RomWBW SCZ180_sc503 |
| Device Programming: | |
| Code size | 512k bytes |
| Checksum | 02EA 42D3 (MiniPro 6.85, SST39SF040) |
| Recommended IC | SST39SF040-70 |
The firmware is supplied (above) as a binary format file, which is suitable for use by most PROM programmers.
RomWBW’s documentation can be found here.
The very latest version, source code and documentation for RomWBW can be found here.
Supported Devices
This version of RomWBW supports the following devices.
| Device | I/O Address |
| Z180 CPU (eg. Z8S180xx), including: * Two asynchronous serial ports * Clock serial I/O for SD card * Timer | 0xC0 (to 0xFF) |
| Memory: (linear, no MMU) 512k Flash, 512k RAM | n/a |
| Z80 SIO dual channel serial #1 Z80 CTC not enabled | 0x80 (to 0x83) |
| Z80 SIO dual channel serial #2 Z80 CTC not enabled | 0x84 (to 0x87) |
| ACIA single channel serial #1 | 0x80 (to 0x81) not enabled |
| ACIA single channel serial #2 | 0x40 (to 0x41) not enabled |
| Real-time clock (DS1302) (shares SD card enable address) | 0x0C |
| Floppy disk (RCWDC) | 0x50 |
| 8-bit IDE direct on CPU bus Compact Flash controller | 0x90 (to 0x97) |
| PPIDE (parallel port IDE) | 0x20 |
| SD card enable bit (shares real-time clock address) | 0x0C |
| USB device #1 (CH375/376) | 0x3E |
| USB device #2 (CH375/376) | 0x3C |
| Front panel / diagnostic LEDs | 0xA0 |
| Front panel config. switches | 0xA0 |
| Status LED | 0x0E |
| Z80 CTC quad counter/timer | not enabled |
| Sound (AY chip) | not enabled |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it. Some additional hardware can be enabled by customising RomWBW, which is quite easy to do.
Supported Cards
This version of RomWBW supports the following Z50Bus cards.
| Z50Bus Card (500 series) | Function | I/O address |
| SC503 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC504 | Compact Flash interface | 0x90 (to 0x97) |
| SC505 | RTC and I2C master | 0x0C |
| SC506 | Digital I/O card (front panel LEDs & switches) | 0xA0 |
| Z50Bus Card (100 series) | Function | I/O address |
| SC127 | Compact Flash interface | 0x90 (to 0x97) |
| SC140 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC144 | RTC and I2C master | 0x0C |
| Z50Bus Card (others) | Function | I/O address |
| LiNC | Digital I/O card (used for diagnostic LEDs) | 0xA0 |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
- Incompatible cards (mutually exclusive):
- SC118, Z80 SBC/processor
- Cards not currently supported:
- SC125, serial (SIO) and timer (CTC) *note
- SC511, serial (SIO) and timer (CTC) *note
Note: Support should be possible through configuration files and rebuilding RomWBW.
Release Notes
The Z180’s internal I/O is set to the range 0xC0 to 0xFF.
OLDER RELEASES
RomWBW v3.4
The latest release of this Firmware is detailed in the table below.
| Name | Wayne Warthen’s RomWBW |
| Platform | SCZ180 |
| Configuration | 503 |
| Release | v3.4.0, 2023-12-31 |
| Download | RomWBW SCZ180_sc503 v3.4.0 Dated 2023-12-31 |
| Device Programming: | |
| Code size | 512k bytes |
| Checksum | 02F4 2B37 (MiniPro 6.85, SST39SF040) |
| Recommended IC | SST39SF040-70 |
| Core Components: | |
| HBIOS | Version 3.4.0, 2023-12-31 |
| Included Apps: | |
| – CamelForth | Version 1.02, 2021-09-07 |
| – CP/M | Version 2.2, CBIOS v3.4.0 [WBW] |
| – Monitor | Version unknown |
| – NASCOM BASIC | Version 4.7b |
| – Tasty BASIC | Version 0.3.0 |
| – Z-System | Version 1.1, CBIOS v3.4.0 [WBW] |
RomWBW’s documentation can be found here.
The very latest version, source code and documentation for RomWBW can be found here.
Supported Devices
This version of RomWBW supports the following devices.
| Device | I/O Address |
| Z180 CPU (eg. Z8S180xx), including: * Two asynchronous serial ports * Clock serial I/O for SD card * Timer | 0xC0 (to 0xFF) |
| Memory: 512k Flash, 512k RAM | 0x78 (to 0x7C) |
| SD card enable bit (shares real-time clock address) | 0x0C |
| Real-time clock (DS1302) (shares SD card enable address) | 0x0C |
| Status LED | 0x0E |
| Diagnostic LEDs / Front panel | 0xA0 |
| Serial #1 (SIO, but no CTC) | 0x80 (to 0x83) |
| Serial #2 (SIO, but no CTC) | 0x84 (to 0x87) |
| 8-bit IDE direct on CPU bus Compact Flash controller | 0x90 (to 0x97) |
| PPIDE | 0x20 |
| Sound (AY chip) | 0x68 |
| Floppy disk | 0x50 |
| USB device #1 (CH375/376) | 0x3E |
| USB device #2 (CH375/376) | 0x3C |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
Supported Cards
This version of RomWBW supports the following Z50Bus cards.
| Z50Bus Card (500 series) | Function | I/O address |
| SC503 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC504 | Compact Flash interface | 0x90 (to 0x97) |
| SC505 | RTC and I2C master | 0x0C |
| SC506 | Digital I/O card (used for diagnostic LEDs) | 0xA0 |
| Z50Bus Card (100 series) | Function | I/O address |
| SC127 | Compact Flash interface | 0x90 (to 0x97) |
| SC140 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC144 | RTC and I2C master | 0x0C |
| Z50Bus Card (others) | Function | I/O address |
| LiNC | Digital I/O card (used for diagnostic LEDs) | 0xA0 |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
- Incompatible cards (mutually exclusive):
- SC118, Z80 SBC/processor
- Cards not currently supported:
- SC125, serial (SIO) and timer (CTC) *note
- SC511, serial (SIO) and timer (CTC) *note
Note: Support should be possible through configuration files and rebuilding RomWBW.
Release Notes
The Z180’s internal I/O is set to the range 0xC0 to 0xFF.
RomWBW v3.2
The latest release of this Firmware is detailed in the table below.
| Name | Wayne Warthen’s RomWBW |
| Platform | SCZ180 |
| Configuration | 503 |
| Release | v3.2.0, 2023-03-18 |
| Download | SC503 RomWBW SCZ180_503 v3.2.0 Dated 2023-03-21 |
| Device Programming: | |
| Code size | 512k bytes |
| Checksum | 02EB 92A1 (MiniPro 6.85, SST39SF040) |
| Recommended IC | SST39SF040-70 |
| Core Components: | |
| HBIOS | Version 3.2.0, 2023-03-18 |
| Included Apps: | |
| – CamelForth | Version 1.02 |
| – CP/M | Version 2.2, CBIOS v3.2.0 [WBW] |
| – Monitor | Version unknown |
| – NASCOM BASIC | Version 4.7b |
| – Tasty BASIC | Version 0.3.0 |
| – Z-System | Version 1.1, CBIOS v3.2.0 [WBW] |
RomWBW’s documentation can be found here.
The very latest version, source code and documentation for RomWBW can be found here.
Supported Devices
This version of RomWBW supports the following devices.
| Device | I/O Address |
| Z180 CPU (eg. Z8S180xx), including: * Two asynchronous serial ports * Clock serial I/O for SD card * Timer | 0xC0 (to 0xFF) |
| Memory: 512k Flash, 512k RAM | n/a |
| SD card enable bit (shares real-time clock address) | 0x0C |
| Real-time clock (DS1302) (shares SD card enable address) | 0x0C |
| Status LED | 0x0E |
| Diagnostic LEDs | 0xA0 |
| Serial #1 (SIO, but no CTC) | 0x80 (to 0x83) |
| Serial #2 (SIO, but no CTC) | 0x84 (to 0x87) |
| 8-bit IDE direct on CPU bus Compact Flash controller | 0x90 (to 0x97) |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
Supported Cards
This version of RomWBW supports the following Z50Bus cards.
| Z50Bus Card (500 series) | Function | I/O address |
| SC503 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC504 | Compact Flash interface | 0x90 (to 0x97) |
| SC505 | RTC and I2C master | 0x0C |
| SC506 | Digital I/O card (used for diagnostic LEDs) | 0xA0 |
| Z50Bus Card (100 series) | Function | I/O address |
| SC127 | Compact Flash interface | 0x90 (to 0x97) |
| SC140 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC144 | RTC and I2C master | 0x0C |
| Z50Bus Card (others) | Function | I/O address |
| LiNC | Digital I/O card (used for diagnostic LEDs) | 0xA0 |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
- Incompatible cards (mutually exclusive):
- SC118, Z80 SBC/processor
- Cards not currently supported:
- SC125, serial (SIO) and timer (CTC) *note
- SC511, serial (SIO) and timer (CTC) *note
Note: Support should be possible through configuration files and rebuilding RomWBW.
Release Notes
Diagnostic LED address has changed from 0x0D to 0xA0.
The Z180’s internal I/O is set to the range 0xC0 to 0xFF.
RomWBW v3.0
The latest release of this Firmware is detailed in the table below.
| Name | Wayne Warthen’s RomWBW |
| Platform | SCZ180 |
| Configuration | 503 |
| Release | v3.0.1, build 2021-10-24 |
| Download | RomWBW-SCZ180_503_v3.0.1_2021-10-24 |
| Device Programming: | |
| Code size | 512k bytes |
| Checksum | 02CF 8BD6 (MiniPro 6.6, SST39SF040) |
| Recommended IC | SST39SF040-70 |
| Core Components: | |
| HBIOS | Version 3.0.1, build 2021-10-24 |
| Included Apps: | |
| – CamelForth | Version 1.02 |
| – CP/M | Version 2.2, CBIOS v3.0.1 [WBW] |
| – Monitor | Version unknown |
| – NASCOM BASIC | Version 4.7b |
| – Tasty BASIC | Version unknown |
| – Z-System | Version 1.1, CBIOS v3.0 [WBW] |
The firmware is supplied (above) as a binary format file, which is suitable for use by most PROM programmers.
RomWBW’s documentation can be found here.
The very latest version, source code and documentation for RomWBW can be found here.
Supported Devices
This version of RomWBW supports the following devices.
| Device | I/O Address |
| Z180 CPU (eg. Z8S180xx), including: * Two asynchronous serial ports * Clock serial I/O for SD card * Timer | 0xC0 (to 0xFF) |
| Memory: 512k Flash, 512k RAM | n/a |
| SD card enable bit (shares real-time clock address) | 0x0C |
| Real-time clock (DS1302) (shares SD card enable address) | 0x0C |
| Status LED | 0x0E |
| Diagnostic LEDs | 0x0D |
| Serial #1 (SIO, but no CTC) | 0x80 (to 0x83) |
| Serial #2 (SIO, but no CTC) | 0x84 (to 0x87) |
| 8-bit IDE direct on CPU bus Compact Flash controller | 0x90 (to 0x97) |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
Supported Cards
This version of RomWBW supports the following Z50Bus cards.
| Z50Bus Card (500 series) | Function | I/O address |
| SC503 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC504 | Compact Flash interface | 0x90 (to 0x97) |
| SC505 | RTC and I2C master | 0x0C |
| SC506 | Digital I/O card (used for diagnostic LEDs) | 0x0D |
| Z50Bus Card (100 series) | Function | I/O address |
| SC127 | Compact Flash interface | 0x90 (to 0x97) |
| SC140 | Z180 processor, including: * SD card enable bit * Status LED * Internal registers | 0x0C 0x0E 0xC0 to 0xFF |
| SC144 | RTC and I2C master | 0x0C |
| Z50Bus Card (others) | Function | I/O address |
| LiNC | Digital I/O card (used for diagnostic LEDs) | 0x0D |
The lack of specific support does not exclude the use of other hardware. It just means the ROM does not do anything specific with it.
- Incompatible cards (mutually exclusive):
- SC118, Z80 SBC/processor
- Cards not currently supported:
- SC125, serial (SIO) and timer (CTC)
- SC511, serial (SIO) and timer (CTC)
Release Notes
The Z180’s internal I/O is set to the range 0xC0 to 0xFF.
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