The KPR-77 was Korg's answer to the TR-606 drum machine. Like the 606, the KPR-77 is basically an analog machine. Its sounds consist of bass, snare, two toms, open and closed hi-hats, accent and (switchable) cymbal/clap. Each drum sound's level can be individual mixed via the sliders. Unfortunately the KPR does not sound nearly as nice as the 606 can. But it has a simple LCD programming display sort of like what the TR-505 sports.
It holds up to 48 patterns (3 groups of 16) and two songs. A pattern can hold up to 32 steps. Like the TR-606, the KPR can be battery operated and REQUIRES batteries for retention of your programmed drum patterns and songs when it is turned off! Fortunately a casette out lets you store its memory to tape for offline storage. The KPR-77 has DIN SYNC IN/OUT as well as Tom trigger outs (like the 606) for external control and triggering. However, Korg's DIN Sync is not the same as Roland's DIN Sync. When syncing Roland and Korg gear via DIN sync, they will work however the Korg machine will run at 1/2 the tempo/speed of the Roland unit. This is because Korg uses a 48 ppqn (parts per quarter note) DIN standard whereas Roland's is 24 ppqn. This can be corrected with several devices which will translate 24-48 sync, such as the Korg KMS-30.