This paper describes a low-cost error control scheme for transmission control based real-time communication, especially for TDMA-implemented Ethernet. As the bandwidth allocation scheme decides the capacity vector (or slot time) based on the worst case condition, there is usually extra available transmission time for each message stream. The proposed error control scheme uses this extra bandwidth for the retransmission of a subpacket, while it needs allocation of additional bandwidth for a retransmission request message. Simulation shows that the proposed scheme enhances the success ratio by 28% at maximum, exhibiting almost error-free transmission when error rate is less than 10/sup -5/ for the given stream sets.