MB87P2020 Datasheet, PDF (338/356 Pages) Fujitsu Component Limited. – Colour LCD/CRT/TV Controller

MB87J2120, MB87P2020-A Hardware Manual
• OFDMA_UL is set to ’0’ for DMA from output FIFO.
In order to avoid this problem the described settings are forbidden for Lavender.
This problem has been solved for Jasmine.
Table 1-8 gives an overview and a classification about the described problem.
Table 1-8: Overview for DMA resistance against wrong settings
Subject
Description
Description
The DMA controller for Lavender may hang if transfer size in DMA
demand mode is equal to ’0’.
Classification
Hint
Effects without
workaround
No DMA transfer is started even if the start condition is met^a.
Solution/Workaround Avoid critical settings IFDMA_LL = 128 and OFDMA_UL = 0.
For Jasmine this problem has been fixed.
Concerned devices
MB87J2120 (Lavender)
fixed for MB87P2020 (Jasmine)
fixed for MB87P2020-A (Jasmine redesign)
Testcase
EMDC: ULB.5 and ULB.13
a. Start condition for input FIFO is: FIFO load <= IFDMA_LL; for output FIFO: FIFO load >= OFDMA_UL.
1. For calculation of data amount not the programmed limits are used but the current FIFO load. Therefore the
data amount is not necessarily ’0’ if the described settings are applied.
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