Macface has 16kB RAM, 2kB EPROM and NMI switch. Around 20 pieces were made.
The extra ROM contains patched NMI procedure (switches to extra RAM then jumps to #0800) and turbo tape loading and saving. Interface is controlled by on-off switch and 3bit latch at #7B (123) address. After reset, all bits are zeroed.
When bit 2 is set, extra RAM is paged in place of ZXROM. When bit 1 is set, this RAM is write-protected (must be paged-in to allow writing).
Bit 0 cooperates with the switch.
|Bit 0||Switch||Extra ROM||LED||Notes|
|0||OFF||disabled||dark||extra RAM or ZXROM in use|
|1||OFF||disabled||dark||port is locked|
|1||ON||disabled||dark||extra RAM or ZXROM in use|
The extra ROM can be detected by PEEKing #0068 (104) address - value #00 means extra ROM is enabled. Standard value in ZXROM is #2A.
The Macface is dedicated to ZX48. To use with ZX128 (two ROM banks) you must switch to OFF position before each reset (and power-on), then select ROM1 (USR 0 in BASIC 128), then you can switch to ON. ROM1 can be also selected by another interface like Timex Interface M-397 or TI-of-TTL.
Files for download
- macface2.zip 58.0kB (2005-07-21 04:58)
- Macface 2.3 documented in Eagle files.
- schem_s.gif 53.6kB (2005-04-18 21:43)
- Macface schematics, original, drawed by hand.
- macface.jpg 30.8kB (2005-04-18 20:32)
- Incomplete Macface owned by author.
- macsoft.zip 19.2kB (2004-09-02 16:09), uploaded by Yarek
- Software for Macface in .TAP format. ROM48, monitor and snapshot saver.
- tr-tap.zip 14.3kB (2002-03-27 01:06)
- Macface can be used to patch ZXROM to allow TR-DOS emulation and TAP file loading under ZXVGS (with external interface: TMX, PLD). See how to program Macface from included source.
- macfrom.zip 1.9kB (2001-12-21 22:06)
- The Macface 2.3 ROM contents.
Links to other pages
- [pl] Author's page