K-2 Electronics

The Kradle was a keyboard and enclosure upgrade for the ZX-81 and TS 1000. It had 50 calculator-style keys (including a full-size space bar and two shift keys), 64K of RAM and  circuitry to improve tape load/save. The Kradle allowed users to copy the ROM to RAM and then turn the ROM off. Unlike some

An add-in expander for the Kradle, providing RS232 and printer/output ports, communication to modem or remote computer plus standard parallel output (8 bit) port with handshaking, hardware UART, software BAUD select, vectored interrupt capability. Requires no memory space; I/O mapped.

Parallel digital input/output (16 lines) expansion option for Kradle. Adaptable to parallel printer port.